This is for a 6-shot 500, here is the same model number on the Mossberg site for confirmation: mossberg.com/store/500-12-gauge-security-barrel-18-5-blued-6-shot-90015.html

Jory, 6 Shot 500. ***Note***: - Will Not Fit Guns With 8-Shot Magazines. ((Features and Specifications)): - Manufacturer Number: 90015 - Mossberg 500 Shotgun Barrel - Cartridge: 12 Gauge - Chamber: 3" - Barrel Type: Smooth Cylinder Bore - Barrel Length:18" - Sight: Bead Front Sight - Finish: Blued. ---- Fits: Mossberg 500 & Maverick 88.