Designed to give you the edge over your competition. Patented, proven push-pin design Quickly and easily attaches to and detaches from the magazine tube No specialty tools or devices required for assembly/disassembly One piece design, no small parts to keep track of Fits the USPSA 140mm guage Holds 20+1 rounds of 40S&W Holds 23+1 rounds of 9mm Easy to load into the gun with fully loaded magazine Adds weight to magazine base to help mags drop free easier for faster reloads Made in the USA