How to mount a Viridian RFX-45 on a Picatinny rail: it is a Aimpoint ACRO / Steiner MPS enclosed-emitter reflex, so it takes a ACRO-plate Picatinny mount. Which mount to buy and the height to pick.

Updated 05 September 2026.

Scope Mount Finder / Every rail, tube and red-dot footprint

Fit a Viridian RFX-45 on a Picatinny rail

Name: Fit a Viridian RFX-45 on a Picatinny rail: published specification
Creator: Scope Mount Finder
License: https://creativecommons.org/licenses/by/4.0/

The Viridian RFX-45 is a Aimpoint ACRO / Steiner MPS optic. Here is the mount that puts it on a Picatinny rail and the footprint it must match.

Direct fitThe Viridian RFX-45 is a Aimpoint ACRO / Steiner MPS enclosed-emitter reflex, so it clamps onto an ACRO-plate Picatinny mount. Buy the ACRO-plate Picatinny mount, not a mount cut for any other footprint.

OpticViridian RFX-45Aimpoint ACRO / Steiner MPS

interface

Mountclosed body clamps an ACRO plate, not a screw-down cut

seats on

RailPicatinny rail (MIL-STD-1913)5.23 mm slot, 10.01 mm pitch

Fit readoutBench figures

Fitment

Optic type

enclosed-emitter reflex

Mount the Viridian RFX-45

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The Viridian RFX-45 is cut to the Aimpoint ACRO / Steiner MPS footprint. To put it on a Picatinny rail you fit a ACRO-plate Picatinny mount: the mount carries the Aimpoint ACRO / Steiner MPS pattern on its top and clamps the rail below, so the sight screws down to the pattern it was made for.

A mount cut for a different footprint will not take the Viridian RFX-45. Match the mount to the Aimpoint ACRO / Steiner MPS pattern, and pick the mount height for the cowitness or heads-up hold you want on the rifle or carbine.

Related fitments

›Viridian RFX-45 footprint and mountthe optic
›Aimpoint ACRO / Steiner MPS footprintthe pattern
›How this footprint reaches a railthe general fit
›Picatinny rail (MIL-STD-1913)the base

Questions and answers

Fit a Viridian RFX-45 on a Picatinny rail?

The Viridian RFX-45 is a Aimpoint ACRO / Steiner MPS enclosed-emitter reflex, so it clamps onto an ACRO-plate Picatinny mount. Buy the ACRO-plate Picatinny mount, not a mount cut for any other footprint.