This is a retainer (or a base lock) for plastic base plates and sleeves on Kahr 9mm magazines. This works with factory base plates or Lakeline LLC base plates.
Sold in the Continental U.S., Alaska and Hawaii only.
WARNING: This product can expose you to chemicals which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.