BT40 Through Coolant Face Mill Arbors 15,000-25,000RPM G2.5/G6.3, BT50 Through Coolant Face Mill Arbors 15,000-25,000RPM G2.5/G6.3, BT30 Face Mill Arbors 20,000 RPM G2.5, BT40 Face Mill Arbors 15,000 - 25,000 RPM G2.5/G6.3 & BT50 Face Mill Arbors 15,000 - 25,000RPM G2.5/G6.3