Genuine factory Glock 19 9mm 10-Round magazines. Polyethylene body with a steel liner. Compatible with the reversible mag release on Gen-4 guns as well as earlier Generations 1-3. Fits flush on the compact frame of the G19 and, but as with all Glock mags, they will still function in the smaller framed sub-compact G26. Will not fit the full size G17 or G34.