This is a factory original equipment manufacturer (OEM) magazine for the Thompson/Center Compass rifle. It works with both .300 Winchester Magnum and 7mm Remington Magnum ammo, and holds four rounds. It’s great to have a few on hand for quick reloading at the range or when hunting. Since they are OEM magazines, you can be sure of getting the same reliable feeding as with the magazine originally supplied with your Compass. 

Specifications and Features
Thompson/Center TC110101
.300 Winchester Magnum or 7mm Remington Magnum 
4 round capacity
Polymer construction
Black