Hoppe's No. 9 Conversion Adapter Slotted End, .410-20-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 .410 to 20-gauge This is a great, easy to use adaptor