Er/Rdt-25 3/8 Tap Collet Premium Quality Er Quick Change Length Compensating Tapping Collets. Converts Any Er Collet Chuck Into A Tapholder. Interchangeable With Br,Dr,Esx & Rd Collets Sealed For Coolant Through Applications. Tested To 1000 Psi. Directs Coolant Out To The Tip Of The Tool. Standard Or Oil Hole Tools. Precision Manufacturing, Made From High Grade Spring Steel, Hardened & Ground With 100% Quality Inspection. Long Life Exceeding Other Collet Types