This is a NCSTAR Magazine Pouch known as the Magazine Wallet, model CMW2937B.
This pistol/rifle magazine wallet provides high capacity storage in a slender profile case. It has a secure full length hook and loop closure and an open flat design to allow rapid access to all magazines.
Features:
Holds up to 8 AR/AK Style Mags, 16 Double Stack Pistol Mags, or 32 Single Stack Pistol Mags