I just got a Sig pouch with some MPX mags.  The pouch only has hook-side Velcro on the back for attachment to gear.  Is this a common way to attach pouches?

I've seen plenty of MOLLE, Alice, belt loops, tech locks, etc, but have not seen this before.

Are adapters available to attach to MOLLE?

Tag for answers as well

sig makes two pouches, both come in black and tan.

the open top, velcro hook back you mentioned and the bungee retention molle backed one.

the velco back is more for use inside cases, which tend to have loop interior.
Hook Back:



The molle back is more for external use, hence the retention.
Molle back:



There are adapter panels for velcro + molle, but they tend to be for adapting molle to velcro-- not the other way around.
Amazon example
I would not strap that on a ruck and hope it works.

Good info.  Thanks!

Guess I'll rivet some MOLLE locks to mine for belt/ MOLLE use.