Turn the Ar-15 into a sub gauge shotgun! Our upper fires .410 shot shells and fits on 5.56 or .223 Ar-15 lowers. Installation is identical to any other upper just drop on your factory lower, use the included bolt carrier group, charging handle, buffer and spring then add the 10 round .410 magazine and thats all it takes to get started. Be sure to check ammo before buying as we have found substantial fluctuations in the over all case length. If you can load it in the mag it will feed. 2.30 inch or less case length worked well in testing. We recommend shooting heavier loads to get your upper broken in. The uppers we tested only needed less than a box of heavy loads before they flawlessly shot the low brass bird shot. Specifications for IMG AR-15 .410 19.25in Complete Upper Receiver w/10 Roumd Magazine: Manufacturer: IMG Caliber: .410 Bore Overall Length: 26 in Barrel Length: 19.25 in Muzzle Device: Muzzle Brake Color: Black Fabric/Material: Polymer Handguard Length: 10.5 in Gun Rail: M-LOK Gun Make: AR Platform Gun Model: AR-15 Weight: 4.2 lb Barrel Material: Aluminum Magazine Included: Yes Mount Type: Picatinny Package Contents: IMG AR-15 .410 19.25in Complete Upper Receiver w/10 Roumd Magazine 410 Complete Upper w/ BOLT CARRIER GROUP AND CHARGING HANDLE What firearm models does the manufacturer say IMG AR-15 .410 19.25in Complete Upper Receiver w/10 Roumd Magazine is compatible with? The manufacturer says that IMG AR-15 .410 19.25in Complete Upper Receiver w/10 Roumd Magazine is compatible with AR-15