Hoppe's No. 9 Conversion Adapter Slotted End, 16-Gauge/12-Guage Can be used with patches Compatible with all HOPPE'S cleaning rods Made of quality materials 100 percent designed and tested Hoppe's No. 9 Conversion Adapter permits interchangeability with non-standard size threads Intended for use with 16-gauge/12-gauge This is a great, easy to use adaptor