Head to head

Holosun 507COMP vs 507C X2: Window, Size and Footprint

By Cole Harlan, EditorUpdated Nov 4, 2026How we verifyEditorial standards

Both mount on Holosun’s RMR footprint, use a CR1632 and carry the same 50,000-hour and IP67 ratings, so the real differences are window, size, weight and reticle. The first column is the HS507COMP-RD (the large-window competition optic); the second is the HS507C-X2, the 507C we chart here. Every figure is copied from Holosun’s own product pages, checked November 4, 2026.

At a glance

Spec (Holosun label)	HS507COMP-RD	HS507C-X2
Window size	1.1″ × 0.87″	0.91″ × 0.63″
Body dimensions	1.8″ × 1.3″ × 1.3″	1.78″ × 1.15″ × 1.15″
Body weight	1.7 oz	1.5 oz
Fitment (maker wording)	Direct Mount, RMR Footprint	Direct Mount, RMR Footprint
Reticle	2 MOA Dot & 8/20/32 MOA Circle	2 MOA Dot & 32 MOA Circle
Reticle system (maker name)	Performance Reticle System (PRS)	Multi-Reticle System (MRS)
Battery	CR1632, side tray	CR1632, side tray
Battery life (setting 6)	50,000 hours	50,000 hours
Brightness settings	8 Daylight & 4 NV	10 Daylight & 2 NV
Solar power	No	Yes
Housing	7075 T6 Aluminum, anodized, black	7075 T6 Aluminum, anodized, black
Submersion	IP67	IP67
Vibration	5000G	5000G
Wavelength	650nm	650nm
Source (checked Nov. 4, 2026)	holosun.com/products/hs507comp-rd	holosun.com/products/hs507c-x2

Holosun names the footprint on both pages as “RMR Footprint” and says it “allows direct mounting to a wide range of optics ready pistol slides.” We have not verified fit on any particular slide. We list no price: neither page prints one.

Other 507C and 507COMP pages

This page charts the 507C X2. Holosun also lists the HS507C-X3-RD, which its page lists with a 0.91″ × 0.67″ window, 1.55 oz body weight and 100,000 hours of battery life at setting 6; the X3 against the X2 is covered in 507C X3 vs X2. Holosun’s HE507COMP-GR is the green-emitter version of the 507COMP: its page lists the same 1.1″ × 0.87″ window, 1.8″ × 1.3″ × 1.3″ body and 1.7 oz weight as the red HS507COMP-RD, with a 540nm wavelength.

Which to pick (on paper)

If window size is the deciding number: Holosun lists 1.1″ × 0.87″ for the 507COMP and 0.91″ × 0.63″ for the 507C X2.
If you want more reticle choices: the 507COMP lists a 2 MOA dot with 8, 20 or 32 MOA circles; the 507C X2 lists a 2 MOA dot and a 32 MOA circle.
If weight and body size matter: the 507C X2 at 1.5 oz and 1.78″ × 1.15″ × 1.15″, against 1.7 oz and 1.8″ × 1.3″ × 1.3″ for the 507COMP.
If you want solar power: Holosun lists Solar Power “Yes” for the 507C X2 and “No” for the 507COMP.
If you need a different footprint: neither; both are RMR. For K-footprint slides see 507C X2 vs 507K X2.

We have not range-tested these; facts below are from the maker.

Frequently asked questions

Do the Holosun 507COMP and 507C X2 use the same footprint?

Yes. Holosun lists both the HS507COMP-RD and the HS507C-X2 as Direct Mount, RMR Footprint.

How big is the 507COMP window compared with the 507C X2?

Holosun lists a 1.1 x 0.87 inch window for the HS507COMP-RD and 0.91 x 0.63 inch for the HS507C-X2.

What reticles do the 507COMP and 507C X2 offer?

Holosun lists a 2 MOA dot with 8/20/32 MOA circle options (Performance Reticle System) on the 507COMP, and a 2 MOA dot with a 32 MOA circle (Multi-Reticle System) on the 507C X2.

Do both use the same battery and have the same water rating?

Yes. Both list a CR1632 in a side tray, 50,000 hours at setting 6, and an IP67 submersion rating.

Holosun 507COMP vs 507C X2: Window, Size and Footprint

At a glance

Other 507C and 507COMP pages

Which to pick (on paper)

Frequently asked questions

Sources

Keep exploring

At a glance

Other 507C and 507COMP pages

Which to pick (on paper)

Frequently asked questions

Sources

Keep exploring

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