8-1/4 O.D. Flush Type Mandrel with 36 Fishing Neck and 6-5

8-1/4 O.D. Flush Type Mandrel with 36 Fishing Neck and 6-5/8 Regular Box Top Connection with Drilco Boreback and 7-13/16 bevel diameter and to have shot peened threads. To have 3 mill slots stenciled with serial number and work order as specified by c