One more interesting product from S&J Hardware: Detachable Shotshell Carrier Pouch MK 2.
Haven’t tested it yet but looks extremely interesting!

Detachable Shotshell Carrier Pouch MK 2

Detachable Shotshell Carrier Pouch MK 2

Detachable Shotshell Carrier Pouch MK 2

Detachable Shotshell Carrier Pouch MK 2

You can get it directly from S&J Hardware