This ETS Group magazine for GLOCK 17 is a 22-round translucent polymer magazine compatible with every generation of 9mm double stack Glock handguns. The proprietary polymer construction is extremely resistant to impacts, temperatures, UV, and harsh chemicals that can adversely effect many other polymer magazines. Unlike many other after market magazines for the Glock, the ETS magazines are fully compatible with both Glock and aftermarket floor plates. Not compatible with the Glock 43.This is a 22 round extended capacity 9x19mm magazine.DISCLAIMER: This product is not manufactured, authorized, endorsed, or warranted by GLOCK. GLOCK does not warrant or represent that this product is compatible with GLOCK pistols.