Magpul Industries, PMAG, D-50, 50Rd Drum, Black, Fits HK94/MP5 Pattern Firearms
 
Next-generation impact, crush resistant polymer construction and corrosion resistant
Bolt hold open feature to lock the bolt back on the last round
Will seat fully loaded on a closed bolt
Ratcheting Loading Lever takes tension off the spring for easy loading by hand
Easy to disassemble for cleaning with only a flat-bladed screwdriver or similar flat-bladed tool
Anti-glare translucent window on rear of drum allows for easy determination of rounds remaining
 
Lightweight but incredibly strong, Magpul's PMAG D-50 MP is a highly reliable, 9x19mm Parabellum, 50-round drum magazine for HK94/MP5 large-format pistols and pistol caliber carbines.It's unique drum configuration keeps the height of the magazine manageable, allowing for prone firing and easier storage. For easy loading, it includes a ratcheting loading lever that removes tension from the internal spring. They've also included a rounds-remaining rear window, a high-visibility follower and a capacity indication roller.