Check the listing for details. Pull Studs BT40 Adaptor CNC Retention Knob Pull Stud NT40 M16 for Milling Holder. Color: Black, Condition: New. Listed at 53.00 USD. OTT40 could used as a transition between BT tool holder and SK Tool Holder. Ten-year pull stud/retention knob manufacturer with a market share of 3,000,000400,000 pieces in stock, complete models and specificationsAutomated mass production for fast deliveryHigh-quality steel guarantees strength and working lifeStrict inspection, elegant appearance, reliable packaging Product Features:Each pull stud is tested thoroughly which ensures its qualityMade from fine alloy steel 20CrMnTi with treatment to HRC53-57Hard outside and soft inside, with higher wear resistance and better toughnessHigh quality black oxide ensures long pull stud life and a non-rusting surfacePrecision turning on all critical surfaceLarge selection for specific machine models, custom design acceptedPacking Details：3pcs OTT40 Pull Stud + Free Shipping LYXC is dedicated to the R＆D of CNC tool holder pull studs, nuts, pull stud and nut wrench/spanner, tool holder locking device etc. The pull studs that we supply are BT series, CAT series, BT-CAT series, MAZAK series with complete specifications.Any questions, please contact us, thanks!!!