12 Gauge (also available in 20 Gauge and .410 bore)
5 rounds (also available with an 8-round tube magazine)
18" (other lengths are also available)
Introduced in 1961, the Mossberg 500 series of shotguns are hammerless pump (slide) action shotguns. They feature a non-detachable tube
magazine below the barrel.
Barrels on the 500 are easily interchanged without tools, so one shotgun can be configured for multiple purposes by swapping in different barrels.