FCW TM Saiga 12K Shotgun Gas Drum Adapter
 
Design for Tokyo Marui Saiga 12K / SBS Shotgun Series
The adapter is also compatible with AW/WE AR gas drum.
Octagram Black Steel Valve with Adjustable Gas Output
Coming with Gas Airtight Rubber, BB Loading Mouth
There's no need to compromise on a brand new Saiga gas magazine.