mossberg shotgun ammo sling (holds 25 shells)made in u.s.a. ace case the mossberg shotgun ammo sling is made in the usa using heavy duty nylon and elastic for the loops. the sling is padded for comfort and adjusts easily to fit all mossberg pump and semi-auto shotguns including the popular mossberg 500. sling adjusts for comfort and carry length. the webbing loops through the swivels on the stock. the sling is 2-inches wide made of black nylon, padded - ammo loops hold 10 shells (20, 12, and 10 gauge shells).