Here we have an end of WW2 production Colt Service Model .22-45 1911a1 Conversion Kit. This allows you to train with .22lr ammunition out of your Colt .45 Auto. This is in the original matching number box with the instruction manual and all the proper pieces that were included. These kits are rare, few were made and even fewer still are in the original box. This is a highly desirable accessory for serious Colt Collectors and you certainly can use it for target practice. This is not a registered part of the firearm and it may be sold without any paperwork.