McMillan now makes 4″ and 6″ picatinny rails that can be installed on stocks and used for attaching bipods, monopods, loops, lights, etc. Both the 4″ & 6 ” pic rails have a hole for a quick detach push button sling loop (not included). Color is Black Anodized.
Picatinny rail sizes:
4″ OAL (over all length), 3″ hole spacing
7″ OAL (over all length), 6″ hole spacing
4 Inch, 6 Inch