ATI 15rd 410 Magazine with speed loader is designed only for use with 2 1/2" Shotgun Shells. *Note- The Omni Hybrid 410 shoutgun only works with 2 1/2" shotgun shells. Please check the length of your shells prior to attempting to fire them. Other cartridges such as 45LC or 45-70 will not operate with this firearm. Magazine will not function with SAFIR Brand T-14 Upper previously imported by American Tactical.