Blueguns Mossberg Model 590A1 Training Guns Not Weighted No Light/Laser Attachment Shotgun w/20in Barrel Blue. Use the Blue Guns Mossberg 590 A1 w/ Manual to arm the shotgun and then take aim lining up shots taking casualties and more with the motion of a shaker. The Blue Guns Mossberg 590 A1 w/ Manual has a working manual and the 20in barrel but it is not weighted so it cannot be used for actual target practice. However the 590 A1 w/ Manual can be used for dry fire training as long as you have a BOARD AND THUMB frame to attach it to. Also includes a bipod adapter and sling swivels a fore end quiver and sling swivels and BAGS that are compatible with the Mossberg 590 A1 shotgun. The 590 A1 w/ 20" Barrel is the most popular Mossberg ever made. It has an A1 metal case and a blued finish. Specifications for Blueguns Mossberg 590 A1 Training Long Gun: Manufacturer: Blueguns Color: Blue Gun Make: Mossberg Gun Model: Mossberg Model 590A1 Gun Type: Shotgun Weighted: Not Weighted Additional Features: w/20in Barrel Package Contents: Blueguns Mossberg 590 A1 Training Long Gun What firearm models does the manufacturer say Blueguns Mossberg 590 A1 Training Long Gun is compatible with? The manufacturer says that Blueguns Mossberg 590 A1 Training Long Gun is compatible with Mossberg Model 590A1Blueguns FS590A1: Mossberg 590 A1 w/20in Barrel Blue