Mesa Tactical LEO Gen 1 Stock Adapter (Mossberg)

Mesa Tactical LEO Gen 1 Tele Stock Kit for Mossberg 500/590 (fits 12g and 20g) 

Allows the attachment of a AR style grip/stock on a Mossberg 500/590

Paid $200, asking $100

I have both Gen 1 and Gen 2 adapters available. Gen 1 was discontinued a few years ago.

Details from Mesa website:

"Use Mesa Tactical’s collapsible stock kits and adapters to install AR-15 adjustable buttstocks and pistol grips onto the venerable Mossberg 500 shotgun platforms for the ultimate in tactical shotgun configuration performance. The LEO adapter is our most basic, best-selling model, and features an optimal stock elevation allowing the use of iron sights or even the bead sight."