The SIG-LOC PRO footprint

Page last updated September 30, 2026. Data compiled September 2026 by Andrew Terrebonne.

ROMEO-X SIG-LOC Pro on P320-pattern slides

Layout: Bottom-mount, like SIG-LOC, over a longer footprint
Screws: Screws from beneath the slide
Driver: T8 Torx
Torque: 20 in-lb
Pattern: proprietary

Schematic, not to scale: top-down, front of the optic up.

Screws and torque from SIG Sauer, ROMEO-X SIG-LOC Pro operator's manual (REV10) ↗. Checked against it September 30, 2026.

What to knowSIG's spec sheet names this footprint SIG-LOC PRO, sold on P320 slides, while plain SIG-LOC goes on the P365 and M17/M18. SIG doesn't say the two interchange, so this entry assumes they don't. Flagged until confirmed.

What uses the SIG-LOC PRO footprint?

1 optic uses it and 1 pistol is cut for it. Torque 20 in-lb. The lists below name each optic, pistol and plate.

Optics using this footprint

SIG Sauer ROMEO-X SIG-LOC Pro

Pistols that mount it with no adapter

SIG Sauer P320 Full-Size / Carry (SIG-LOC PRO slide)

Check a pairing

The fit checker tells you whether a specific optic and pistol go together, and what it costs to mount.

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