The Ruger BX-25 is a genuine 25 round magazine that has been tested and proven to feed as reliably as the standard BX-1 10-round Ruger rotary magazine. It features a stainless steel constant-force spring that provides feed consistency round after round.
Specifications:

Caliber	22 LR
Capacity	50
Finish	Black
Model	10/22
Material	Polymer
Type	Detachable
Model Fit	10/22 Series
Brand Fit	Ruger
Max Capacity	50