Mossberg 500 FLEX All-Purpose | 12 Gauge | 28in | 50121

The Mossberg 500 FLEX All-Purpose (model 500, Mfr. part number 50121) is a modular pump-action shotgun built on the proven 500 platform and configured for 12 gauge with a 28-inch vent-rib, ported barrel and a 3″ chamber. The FLEX system uses a Tool-Less Locking System (TLS) to allow quick interchange of the stock, forend and recoil pad without tools. The package includes Accu-Set choke tubes (Full, Modified and Improved Cylinder) and dual/twin bead sights for straightforward patterning and target acquisition.

Designed for versatility, the All-Purpose configuration suits field hunting and clay/sporting applications where quick adaptability and reliable manual operation are priorities. The synthetic Flex stock and vented recoil pad help manage recoil during extended use in the field or on the range.

Product Specifications

• The manufacturer is Mossberg.
• The model is 500 FLEX All-Purpose.
• The manufacturer’s part number is 50121.
• The caliber/gauge is 12 Gauge.
• The barrel measures 28 inches and is a vent-rib ported barrel.
• The chamber accepts 3-inch shells.
• The action type is pump action.
• The finish is Matte Blued.
• The stock material is black synthetic.
• The overall length is 48.25 inches.
• The unloaded weight is 7.5 pounds.
• The included choke tubes are Full, Modified, and Improved Cylinder.
• The sighting system is dual/twin bead sights.
• The UPC is 015813501217.

The FLEX All-Purpose is intended for shooters who want a reliable, manually operated shotgun that can be adapted to multiple roles without tools. Its vent-rib barrel and Accu-Set chokes provide controllable shot patterns for sporting uses, while the synthetic Flex stock and TLS make it easy to tailor fit and switch components based on user preference or mission profile.

Owners commonly praise the platform’s long-standing reliability and the FLEX system’s straightforward modularity.

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