Primary Arms SLx Top Cap RMR Mount - 34mm

The Primary Arms SLx Top Cap Reflex Mount (34mm) adds an offset red dot to a rifle running a 34mm SLx scope mount. It replaces the top cap on the mount and holds a mini reflex sight at the 12 o'clock position directly above your scope, so when a target closes to short range, you lift your head slightly and you're on the dot. It's the clean way to cover close-range transitions without giving up your magnified 34mm LPVO or variable scope.

The top-mounted (piggyback) layout has a real edge over the common 45-degree offset dot: sitting straight up top, it works no matter which shoulder you're shooting from, and it gives you more ways to catch the dot than a side-canted mount. It's machined from 6061 aluminum with a hardcoat anodized finish, weighs about an ounce, and carries Primary Arms' lifetime warranty.

It uses the popular Holosun 507C footprint, so it accepts the Primary Arms Classic 24mm mini reflex or any 507C-footprint optic like the Holosun 507C or 407C.

Important: this is the 34mm version, designed specifically for the 34mm SLx scope mounts. It fits the SLx Cantilever 34mm Mount. It will not fit 30mm mounts (use the 30mm top cap for those) or the older Primary Arms Deluxe scope mounts. Browse the rest of our optics and mounts here.

Key Features

• Offset red dot, up top. Mounts a mini reflex at 12 o'clock for fast close-range transitions.
• Ambidextrous. Works from either shoulder, unlike a 45° side offset.
• 507C footprint. Fits the PA Classic 24mm reflex and any Holosun 507C-footprint optic.
• For 34mm SLx mounts. Purpose-built for the 34mm cantilever mount.
• Light and tough. 6061 aluminum, hardcoat anodized, ~1 oz.
• Lifetime warranty. Backed by Primary Arms.

Specs

• Type: Top-cap piggyback reflex (red dot) mount
• Fits: 34mm SLx scope mounts (1.5")
• Optic footprint: Holosun 407C/507C
• Material: 6061 aluminum
• Finish: Hardcoat anodized, black
• Torque: 16–18 in-lbs
• Weight: ~1 oz
• Warranty: Primary Arms lifetime

FAQ

What does this do?
It replaces the top cap on your 34mm SLx scope mount and holds a red dot directly above your scope, so you can transition from your magnified optic to a red dot for close-range targets by lifting your head slightly.

What red dots fit it?
Any optic with the Holosun 507C footprint, including the Primary Arms Classic 24mm mini reflex, the Holosun 507C, and the 407C.

Will it fit my scope mount?
It fits the 34mm SLx scope mounts (the 1.5" cantilever). It does not fit 30mm mounts (get the 30mm top cap for those), and it does not fit the older Primary Arms Deluxe line, only the current SLx mounts.

Why top-mount instead of a 45° offset dot?
A top-cap dot works from either shoulder and gives you more ways to pick up the dot, where a 45° offset only works shouldered on one side. The tradeoff is height; make sure it clears any tall scope turrets on your setup.