This is a 3 round detachable 8mm Mauser and .30-06 magazine for the Mauser 98.
Modern manufacture, a straight swap for the military format floorplate in the Mauser 98. Accepts .30-06 family cases including .270 and .25-06 as well as 8mm Mauser.
The magazine is designed for round nose bullets, if you are using Spitzer (pointed) bullets you will need to modify the magazine slightly by filing a U shaped notch in the front of the magazine for clearance.
Fits most Mauser 98s, some fitting may be required with tolerance variations between rifles.