ITP Styli
Industrial metrology probing elements for CMMs, Machine Centres and Gear Checking. M2 to M8 thread sizes — ruby to carbide, titanium to carbon fibre. Best price. Best service. Best quality.
🚚 Free Next-Day Delivery on orders over £50
⚡ Same-day dispatch before 4:30pm Mon–Fri
📞 Expert advice: 01732 887334
🕐 Mon–Thurs 8:30–17:30 · Fri 8:30–16:30
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The Full Range of ITP Styli
From straight styli for simple features to star configurations for complex geometries — find the right probe for every measurement task.
The most commonly used stylus. Ball or pointed tip with single and multiple-stepped stems for direct contact inspection.
→Measure large diameters, undercuts and threads without bending risk. The most versatile stylus configuration available.
→Reach into hard-to-access areas or keep multiple probes apart. Short and rigid for maximum measurement accuracy.
→Central interface between CMM, probe and workpiece. Many feature integrated electronic ID chips for precise probe identification.
→For measuring when a ball cannot reach the optimal point. Ideal for punched holes and sheet metal scanning applications.
→Precision ball sections for measuring large inside diameters and integrated undercuts. Available in multiple thicknesses and diameters.
→Large probe ball diameter with reduced weight. The entire hollow hemisphere surface is available for probing, including stem direction.
→Quickly change probe configurations with precision. Integrated electronic ID chips enable accurate identification across all CMM systems.
→Calibration spheres, wrenches, cleaning kits and everything you need to keep your probing system performing at its best.
→Precision Built Into Every Probe
Founded in 2003, ITP Styli has built its reputation around a simple promise: best price, best service, best quality — without compromise. Serving the industrial metrology market for over 20 years, ITP offers the most comprehensive range of CMM styli and accessories for all probe systems.
Every stylus is manufactured to tight tolerances with materials chosen for the application — ruby and silicon nitride balls, titanium and carbon fibre stems, steel and ceramic shanks. Thread sizes M2 through M8 ensure compatibility with coordinate measuring machines, machine tool probes and gear measurement systems from all major manufacturers including Zeiss, Renishaw, Hexagon and Mitutoyo.
"If you are not completely satisfied with our catalogue items, we will fix the problem to your satisfaction or provide a full refund, hassle free."
Protool Ltd — Unit 1 Invicta Business Park, London Road, Wrotham, Kent, TN15 7RJ
📞 01732 887334 · Mon–Thurs 8:30–17:30 · Fri 8:30–16:30
0+
Years in
Metrology
M2–M8
Thread
Sizes
100%
Satisfaction
Guarantee
5%
Below the
Lowest Price
Complete Range
Everything You Need for Precision Measurement
Compatible with all major CMM manufacturers — cross-reference any competitor code to find the equivalent ITP item at itpstyli.com.
Why Choose ITP
The ITP Promise
Best Price
Since founding in 2003, ITP prices to be 5% below the lowest competitor — without sacrificing quality or service. You should never pay more for the precision you need.
Best Quality
Unconditional satisfaction guarantee — if you're not completely happy, ITP will fix the problem or provide a full refund, hassle free. ISO quality certified manufacturing.
Best Service
Styli and accessories are ITP's only focus. Deep application knowledge, comprehensive stock, and a dedicated team — meaning faster answers and better support.
Customer Reviews
What Our Customers Say
Great value styli — identical quality to OEM replacements at a fraction of the price. Delivery was next day too. Will be ordering all our styli through Protool from now on.
Aerospace Manufacturer, Kent
We run Zeiss and Renishaw machines and the ITP styli fit perfectly. Accuracy is spot on and the range means we can get everything from one place.
Automotive Tier 1 Supplier
Ordered a star stylus configuration we couldn't find elsewhere. Protool had it in stock and the technical team helped confirm the right spec. Exceptional service.
Precision Engineering Ltd
The cylinder styli for our sheet metal inspection program work perfectly. Measuring punch hole endpoints is now consistent and reliable. Really impressed.
Sheet Metal Fabricator, Surrey
Fast dispatch, well packaged and consistently accurate. We use the adaptor plates with active ID chips and they've been flawless in our automated inspection cells.
Medical Device Manufacturer
Switched from OEM styli to ITP about two years ago. Not noticed any difference in quality but have saved significantly on consumable costs. Recommended without hesitation.
General Engineering, Midlands
CMM Styli Guide
CMM Styli — A Complete Guide for UK Engineers
Whether you run a Zeiss, Renishaw, Hexagon or Mitutoyo coordinate measuring machine, the stylus is the single component that determines measurement accuracy. At Protool we stock the full ITP Styli range — the most comprehensive selection of CMM styli and probe accessories available online in the UK. With same-day dispatch and free next-day delivery on orders over £50 ex VAT, getting the right stylus to your inspection department has never been easier.
What is a CMM Stylus?
A CMM stylus (also written as CMM styli in the plural) is the precision probing element that physically contacts a workpiece during coordinate measurement. Attached to a CMM probe head, the stylus tip records X, Y and Z coordinates at each contact point, allowing the machine to build a complete dimensional picture of the part. The accuracy of every measurement — whether you're checking flatness, roundness, bore diameter or positional tolerances — depends directly on the quality of the stylus you use.
ITP Styli has manufactured precision CMM styli since 2003 and supplies thread sizes from M2 to M8, covering coordinate measuring machines, machine tool probing systems and gear measurement equipment from all major manufacturers.
Types of CMM Styli
Choosing the right stylus type is the first decision. Each configuration suits a different class of measurement task:
- Straight Styli — The most widely used type. A ball tip on a straight stem, available in single or multiple-stepped configurations. Ideal for most standard inspection tasks where direct contact with the feature is possible.
- Star Styli — Multiple probe arms radiating from a central hub. Allows measurement of large diameters, undercuts and threads without the probe arm bending, even at long gauging lengths. Particularly useful for complex prismatic parts.
- Cylinder Styli — A cylindrical rather than spherical probe tip. Used when the ball cannot reliably reach the measurement point, for example when scanning the endpoints of punched holes in sheet metal.
- Disk Styli — Spherical disc sections for measuring large inside diameters and undercuts that neither a ball nor a cylinder can access. Only suitable for radial probing unless fitted with radius end rollers.
- Hemispherical Styli — Large-diameter ball with reduced weight. The entire hollow hemisphere surface is available for probing, including in the stem direction — unlike disc styli.
CMM Styli Ball Materials
The probe ball material governs wear life, surface friction and measurement repeatability. ITP supplies styli in all standard ball materials:
- Ruby (Synthetic Corundum) — The industry standard. 99% aluminium oxide, extremely spherical, high hardness and low friction on most workpiece materials. The correct choice for the majority of steel, cast iron and alloy measurements.
- Silicon Nitride — Lower density than ruby and electrically conductive. The preferred ball material when scanning aluminium or other non-ferrous surfaces where ruby can cause material pickup and measurement error.
- Zirconia — Higher toughness than ruby. Recommended for scanning on stainless steel and other materials prone to causing abrasive wear on ruby balls.
- Carbide (Tungsten Carbide) — Extremely hard and wear-resistant. Used for pointed-tip styli and applications involving highly abrasive workpiece materials.
- Diamond — Maximum hardness. Reserved for specialist applications on very hard or highly abrasive surfaces where no other ball material provides acceptable tool life.
CMM Styli Stem Materials
The stem connects the ball to the thread and must be as short and rigid as possible. ITP offers four main stem materials to suit different measurement environments:
- Stainless Steel — The standard material. Good rigidity-to-weight ratio for short to medium-length styli. Suitable for the vast majority of CMM applications.
- Titanium — Approximately 40% lighter than steel at equivalent stiffness. The preferred material for longer styli where reduced deflection under preload force is critical to accuracy.
- Carbon Fibre — Maximum stiffness-to-weight ratio. Used for very long extensions and multi-stylus configurations where minimising bending error at the tip is the primary requirement.
- Ceramic (Aluminium Oxide) — Thermally stable and electrically non-conductive. Used in high-temperature measurement environments or where electromagnetic interference could affect probe triggering.
CMM Styli Thread Sizes: M2 to M8
CMM styli use metric threads to connect to probe heads and extensions. The thread size determines which probe heads and extenders the stylus is compatible with. ITP supplies the complete range:
- M2 — Smallest thread, used on compact probes and micro-measurement applications.
- M3 — The most common thread size in general CMM use. Compatible with Renishaw TP2, TP20, TP200, SP25, REVO and many other widely used probe heads.
- M4 — Intermediate size bridging M3 and M5, used on selected probe and extension systems.
- M5 — Standard for larger probe systems including Zeiss RDS and many legacy Zeiss, DEA and LK probe heads.
- M6 / M8 — Larger thread sizes for heavy-duty tactile probing and specialist measurement applications.
If you are unsure which thread size your probe head uses, our team can help — call 01732 887334 or use the ITP cross-reference tool at itpstyli.com to find your exact equivalent.
Renishaw, Zeiss, Hexagon & Mitutoyo Compatible CMM Styli
One of the most common questions we get is: "Are ITP styli compatible with my machine?" The answer is yes. ITP Styli manufactures to the same thread standards and dimensional tolerances as OEM suppliers, ensuring drop-in compatibility across all major CMM brands:
- Renishaw compatible styli — M3 thread styli compatible with TP2, TP6, TP20, TP200, SP25M, REVO RSP3 and PH10 probe head systems.
- Zeiss compatible styli — M5 thread styli for VAST, RDS-CAA, PRECITEC and legacy Zeiss probe systems.
- Hexagon (Brown & Sharpe / DEA) compatible styli — Full range covering HP-S-X1H, HP-TM and other Hexagon probe families.
- Mitutoyo compatible styli — M3 and M5 options for CRYSTA series and Bright Apex CMMs.
- Moog/DEA, LK Metrology and FARO — ITP styli are also available for these less common but widely used CMM platforms.
ITP's cross-reference database covers hundreds of OEM part numbers. If you know your existing Renishaw, Zeiss or Hexagon stylus reference, you can find the equivalent ITP item directly at itpstyli.com — typically at a significantly lower price with no reduction in accuracy or durability.
CMM Extensions, Adaptors and Accessories
The stylus alone is only part of the measurement system. For complex parts where the probe head cannot be positioned close to the feature being measured, CMM styli extensions extend the reach of the probe while maintaining rigidity. ITP supplies extensions in stainless steel, titanium and carbon fibre across all standard thread sizes.
CMM adaptor plates and holders form the mechanical interface between the probe head and the stylus or stylus cluster. Modern ITP adaptor plates feature integrated electronic identification chips compatible with Renishaw and Zeiss auto-jointing systems, allowing automated stylus changing without loss of qualification data. Star stylus holders allow multiple styli to be configured in fixed clusters for measuring features in different directions within a single measurement program.
Completing the range, ITP CMM accessories include calibration spheres, stylus cleaning tools and wrenches for assembly and disassembly. Using the correct torque when fitting styli is important — over-tightening can cause stem breakage while under-tightening introduces measurement error through stylus slip.
How to Choose the Right CMM Stylus
Selecting the right stylus for your application comes down to four key rules used by metrology engineers worldwide:
- Use the shortest stylus possible. Every millimetre of stylus length amplifies angular errors from probe lobing and deflection. The shorter the stylus, the more accurate and repeatable the measurement.
- Use the largest ball possible. A larger ball is less susceptible to surface roughness and contamination at the contact point, and reduces the effect of ball form error on measurement results.
- Minimise the number of extensions and joints. Each threaded joint is a potential source of compliance and misalignment. Only use extensions when the feature genuinely cannot be reached without them.
- Match the ball material to the workpiece. Use ruby for steel, silicon nitride for aluminium, zirconia for stainless steel. Wrong ball material causes rapid wear and measurement drift.
Not sure which stylus is right for your application? Our technical team has over two decades of metrology experience and can recommend the correct configuration for your specific probe head, part geometry and inspection program. Call us on 01732 887334 — Mon–Thurs 8:30–17:30, Fri 8:30–16:30.
Buy CMM Styli Online in the UK — Next-Day Delivery from Protool
Protool is one of the UK's leading online suppliers of ITP precision CMM styli, with the full range in stock and ready to ship. Order before 4:30pm Monday to Friday for same-day dispatch, with free next-day delivery on all orders over £50. We serve metrology departments, quality control teams and engineering workshops across the UK — from single stylus replacements to full probe system kits.
Unlike buying direct from an OEM, ITP styli from Protool are priced to be the best value in the market, backed by a 100% satisfaction guarantee. If the product doesn't meet your expectations, we'll replace it or refund you in full — no questions asked. Browse the full range using the categories above or call our team for a recommendation tailored to your machine and application.
Shop ITP Styli at Protool
The UK's leading supplier of ITP precision styli. Free next-day delivery on orders over £50 ex VAT. Call our team on 01732 887334 for expert guidance.
