Yes .. ;lkjkl
Yes it is 00
4.68" is the length
you would need about 5 slots
The FAB Defense Rubber Over Molded Ergonomic Foregrip will fit to any 1913/picatinny rail. Ensure you check local, state, and federal laws before purchasing a vertical foregrip.
The FAB Defense Rubber Over Molded Ergonomic Foregrip mounts to standard picatinny/1913 rail systems. However, you can use an Mlok to picatinny rail segment that allows you to utilize picatinny attachments on your Mlok rail.
Unless the shotgun has a picatinny rail for this to mount underneath the shotgun. It will not fit it.
This needs approximately 2.13 in of a picatinny rail.
It looks like it should mount on the picatinny rail on the Landor Arms semi-auto 12 gauge LND-3XX series.
It will work on the Rock Island VR80, but you will need to use an M-LOK picatinny rail section to mount it on.
https://www.opticsplanet.com/bravo-company-mfg-mlok-3-inch-polymer-picatinny-rail-section.html