MRS (Multiple Reticle System) cycles through three fixed presets: dot only, circle only, or circle-dot. CRS (Competition Reticle System) provides four independent elements — a 2 MOA center dot, an 8 MOA ring, a 20 MOA ring, and a 32 MOA ring — each switchable on or off independently. The shooter configures any combination they want, and the optic stores that setting. All configurations share the same zero; switching between them requires no re-zeroing. CRS supports combinations MRS cannot produce, such as the dot paired only with the 8 MOA inner ring, or the 20 and 32 MOA rings together without a center element.

The 507COMP green variant is NV compatible, which is different from the HE508T-GR-X2 green model, which is not. The distinction comes down to the specific LED emitter and driver electronics used in each product. The 507COMP’s green LED can be dimmed to the low-output levels required for NV compatibility at its two dedicated NV brightness settings. If you previously saw that the HE508T-GR-X2 is NV non-compatible and assumed all Holosun green optics share that limitation, that assumption does not apply here. Both the red HS507COMP and the green HE507COMP-GR are NV compatible. For the HE508T platform specifically, the green model is not NV rated; for the 507COMP platform, both colors are.

Both models use the same 507COMP platform: identical 1.1 by 0.87 inch window, CRS reticle system, 7075-T6 aluminum housing, Shake Awake, 50,000-hour CR1632 battery life, 8 brightness settings with 2 NV-compatible levels, and limited lifetime warranty. The differences are reticle color and price. The green HE507COMP-GR is $399.99; the red HS507COMP is $369.99. For competition shooters, the green reticle can appear sharper and faster to pick up in daylight because the human eye is most sensitive to green wavelengths. Whether that advantage is worth $30 is a personal preference call. Unlike the HE508T platform where the green model loses NV compatibility, both 507COMP variants maintain full NV compatibility.

The 507COMP uses the same mounting footprint as the standard 507C and Trijicon RMR, so it seats on any slide cut for those optics. The 507COMP’s larger window makes its body physically wider than the standard 507C, and holsters designed around the 507C body profile may not clear the 507COMP’s housing. Confirm with the holster manufacturer that their 507C model also fits the 507COMP before ordering. Most major competition holster makers produce 507COMP-compatible fits as a distinct SKU.

The HE507COMP-GR uses a CR1632 3V lithium coin cell — not the CR2032 used in Trijicon RMR optics and many other pistol dots. The two are not interchangeable. CR1632 batteries are widely available at electronics and hardware retailers. The battery is accessed via a side-loading tray without removing the optic from the slide, so battery changes do not require a re-zero.