This magazine is for the KWA M9 PTP NS2. This only fits the new KWA M9 and will not fit the older KSC or KWA M9 airsoft pistols. The reinforced design features a screwed on baseplate to prevent breakage.
On older KWA M9 PTP Magazines, if the mag was dropped, the baseplate could break off. To remedy this, KWA has installed two screws through the basepad on each magazine, which makes the bottom of the magazine much stronger.