Mossberg Barrel, 12 Gauge, 20 Vent Rib, M500, AccuSet Chokes, Blue, Bead Sight, Ported 90140 20" All-Purpose barrel with vent rib" dual bead sights" smoothbore" and blued finish. Includes Accu-Choke set (Improved Cylinder" Modified" Full) and choke tube wrench. Compatible with 12 Gauge Mossberg 500 and Maverick 88 6-shot models.