wow this thread is really old but here goes, the ccworks 12ga tac strippers are available in 4&6 rd count 3 colors,and 5 mounting solutions, the orig. ss hd spring clip,the GI UM-84 that also take a cover just for the 6 rd,the blade tech tek-lok,the safailand els system, and the G-CODE RTI system. I now also offer a constant tension leaf spring just for the 4 rounders as an option + $6.00 and of course all the variants can be ordered to reto fit early product, the 6 rd backs fit the choate speed strippers. and one last thing that no one else mentioned is the best feature of all, with out the spacers installed they will hold most 223 magazines!!! so it's a better deal all around for novice 3 gunner.