THIS IS A COLLIS MODEL #78957 #3 QUICK CHANGE TAP ADAPTER. IT IS AN INDIVIDUAL TAP ADAPTER WITH A 1-3/8" TAP SIZE. THE ADAPTER FEATURES A 1.108" TAP SHANK DIAMETER AND AN ADAPTER RANGE DESIGNATED AS #3. ITS DIMENSIONS INCLUDE A 2.75" DIAMETER, 0.55" LENGTH, AND A 2.79" TAP ENTRY DEPTH. THE UNIT IS DESIGNED FOR TOOLING NEEDS, OFFERING RELIABLE COLLIS QUALITY.