Mossberg Expands the 500 FLEX System with New 20-Gauge Shotgun Offerings

20-Gauge Pump-Actions that Accept TLS Accessories for Added Versatility.

Mossberg FLEX modular 500/590 shotguns
Mossberg FLEX modular 500/590 shotguns

North Haven, CT –-( When introduced in 2012, the innovative, patented and patent-pending system of Mossberg FLEX modular 500/590 shotguns and interchangeable TLS (Tool-less Locking System) accessories provided unprecedented versatility and the ease of converting your 12-gauge 500/590 shotgun in seconds without the need for tools.

Now Mossberg has expanded the line to include 20-gauge with the introduction of four new 500 FLEX 20 gauge pump-action shotguns; available in hunting and tactical base models.

At the core of the 500 FLEX System is the patented “TLS,” a series of three connectors that allow stocks, forends and recoil pads to be switched for a variety of hunting/shooting applications or to easily re-configure your Mossberg FLEX shotgun to fit individual lengths of pull. Stocks can be interchanged with the simple lift and turn of the TLS latch on the receiver; remove the stock and slide the replacement stock onto the connector. Once aligned, simply turn the TLS latch 90 degrees clockwise and close the latch, locking the stock firmly in place. Forends and recoil pads are designed with TLS release buttons; when pushed, allow for the replacement of those components. Choose from 16 FLEX TLS accessories and Mossberg’s versatile line of 500 20-gauge accessory barrels to convert your base gun into a multi-purpose shotgun.

500 FLEX Hunting 20-Gauge Shotguns – The hunting models feature standard forends and full-length stocks with medium recoil pad; front mag cap and rear sling swivel studs; Mossberg’s universally-recognized, ambidextrous top-mounted safety; and optional black synthetic or Mossy Oak Break-Up Infinity® camo stocks and forends. These low-recoiling, 20 gauges accept 2 ¾ or 3-inch shotshells with a maximum capacity of six rounds.  The 500 FLEX Hunting 20 Gauge (54319) features OD Green metal finishes and Mossy Oak Infinity-covered stock and forend; compact 24-inch vent rib barrel with X-Factor™ Ported choke tube, ideal for turkey hunting; and fiber optic sights, adjustable for windage and elevation. The 500 FLEX Hunting 20 Gauge (54316) comes with standard matte blue and black synthetic finishes; 26-inch vent rib barrel with Full, Modified and Improved Cylinder ACCU-CHOKE™ tubes; and twin bead sights. MSRP: $484 – $591.

500 FLEX Tactical 20-Gauge Shotguns – The 20-gauge, 3-inch personal defense shotguns feature cylinder bore barrels; matte blue metal finishes and black synthetic stocks and forends; tactical forend with Picatinny tri-rails and convenient touchpad for ease of adding lights or accessories; choice of 6-position adjustable or pistol grip stock; 6-round capacity   (2 ¾ inch); front mag cap and rear sling swivel studs; and Mossberg-standard top-mounted safety. The 500 FLEX Tactical Adjustable 20 Gauge (54318) has a 6-position adjustable stock (11 – 14 ¼-inch LOP) and compact 20-inch barrel with single bead sight. The 500 FLEX Tactical Cruiser 20 Gauge (54317) is equipped with a pistol grip and 18 ½-inch stand-off barrel with white dot sight. MSRP: $577 – $643.

Don’t forget the base platform of this ultimate, adaptive shotgun is the legendary 500 and comes with a ten-year limited warranty. And the versatility of the FLEX System extends beyond your 20-gauge shotgun as all TLS FLEX accessory components will fit your 20 gauge 500 FLEX, 12-gauge 500/590 FLEX shotguns and MVP™ FLEX™ bolt-action rifles (stocks and recoil pads only).

Start “FLEXing your Mossberg” today with the most-innovative concept in shotgun customization; now available in 20-gauge! For complete specifications on the Mossberg FLEX Series (pump-action shotguns and MVP bolt-action rifles) and TLS accessory system, please visit our web site at

Mossberg FLEX Series Shotgun Specifications:









54319500 Hunting20 ga3 in624 in VROD GreenAdjustable Fiber OpticX-Factor PTDStd SyntheticInfinityStd SyntheticInfinityMedium$591
54316500 Hunting20 ga3 in626 in VRMatte BlueTwin BeadACCU-SETStd SyntheticBlackStd SyntheticBlackMedium$484
54318500 TacticalAdjustable20 ga3 in620 inMatte BlueBeadCylinder BoreTactical Synthetic Black6-Pos Adj Synthetic BlackMedium$643
54317500 TacticalCruiser20 ga3 in618 1/2 in Stand-OffMatte BlueWhite DotCylinder BoreTactical Synthetic BlackPistol Grip Synthetic BlackMedium$577


Mossberg FLEX Series Accessories Specifications:

95210FLEX Recoil Pad Assembly  – 3/4 inch (SMALL)$27
95211FLEX Recoil Pad Assembly  – 1 1/4 inch (MEDIUM)$27
95212FLEX Recoil Pad Assembly – 1 1/2 inch (LARGE)$40
95213FLEX Tactical Tri-Rail Forend – Black$52
95214FLEX Standard Forend – Black$36
95216FLEX Standard Forend – MOBU Infinity$52
95217FLEX Standard Forend – Realtree MAX-4$52
95218FLEX Pistol Grip – Black$31
95219FLEX 6-Position Adjustable Stock – Black$117
95221FLEX 4-Position Adjustable Hunting Stock with Dual Comb – Black$157
95222FLEX 4-Position Adjustable Hunting Stock with Dual Comb – MOBU Infinity$171
95223FLEX Standard Stock 12 ½-inch LOP – Black (Compact)$84
95224FLEX Standard Stock 14 ¼-inch inch LOP – Black (Full-Length)$84
95226FLEX Standard Stock 13 ½-inch LOP – Black (Medium)$84
95227FLEX Standard Stock 13 ½-inch LOP – MOBU Infinity (Medium)$106
95228FLEX Standard Stock 13 ½-inch LOP Realtree MAX-4 (Medium)$106


Mossy Oak Break-Up Infinity is a registered trademark of Haas Outdoors, Inc.  Realtree MAX-4 is a registered trademark of Jordan Outdoor Enterprises, Ltd.


About O.F. Mossberg & Sons, Inc.

Founded in 1919, O.F. Mossberg & Sons, Inc. is the oldest family-owned firearms manufacturer in America, and is the largest pump-action shotgun manufacturer in the world. Leading the way with over 100 design and utility patents to its credit, and standing as the first ISO 9001 Certified long-gun manufacturer, Mossberg is considered to be one of the most innovative firearms manufacturers in U.S. History. For more information on commercial, special purpose, law enforcement and military shotguns, rifles and accessories, please visit their website at

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