It does need an adapter to mount on a pic rail.
We offer multiple different mounts from B&T, Scalarworks, and Reptilia on the Aimpoint Inc. USA website. Our B&T QD mounts are the P/N 200517, 200518, and 200519 which are 22mm, 30mm, and 39mm respectively. If you don't want a QD mount, the P/N 200666 ACRO 22mm mount also works great.
The Reptilia and Scalarworks mounts are sold as a package that can be purchased from our website.
Thanks,
Tony
Commercial Sales Support
AimPoint inc.
In order to mount the Aimpoint ACRO P-2 to a Picatinny rail, you will need an ACRO specific mount. The ACRO P-2 uses the proprietary ACRO footprint and will not mount directly to the rail alone.