HiViz FastDot H3 Sight Set for Sig P320 - Model SG320FD21

The HiViz FastDot H3 sight set for Sig P320 combines fiber optic and tritium illumination in a low-profile design built for shooters who need reliable sight visibility across changing light conditions. Whether you're training at the range in bright daylight or responding in low light, this dual-illumination system keeps your front and rear sights visible without battery dependence. The red fiber optic front sight pairs with a green tritium rear sight, giving you the speed of fiber optics when light is available and the dependable glow of tritium when it isn't.

Built entirely from steel, the FastDot H3 maintains a slim profile that won't interfere with standard holster fit—important if you're carrying your P320 daily or running it from your duty rig. The sights are engineered to work with fixed-sight Sig P320 models (and compatible P365 frames) that don't have optics-cut slides; if your gun is set up for a red dot, these aren't the right choice. The patented H3 tritium technology is what sets this system apart: true 24-hour illumination without the bulk of older tritium designs, wrapped in a professional package that works as hard as you do.

Installation should be handled by a qualified gunsmith to ensure proper alignment and function. HiViz backs these sights with a 12-year warranty against tritium failure due to defects in material or workmanship under normal use—a confidence vote in durability that matters when your sights are part of your self-defense setup.

Key Features

• Dual-illumination design: fiber optic front (red) with tritium rear (green) for all-light-condition visibility
• Low-profile construction fits standard Sig P320 holsters without modification
• All-steel construction for durability and reliability
• 24-hour tritium illumination independent of ambient light or batteries
• Patented H3 tritium technology with proven brightness and longevity
• Compatible with fixed-sight P320 and P365 models only (non-optics-ready slides)

Specifications

Frequently Asked Questions

Will these sights fit my Sig P320 with an optics-ready slide?

No. The FastDot H3 is designed for fixed-sight P320 and P365 models only. If your slide is cut for a red dot or other optic, these sights are not compatible.

Do I need batteries or charging for the tritium to work?

No. Tritium is self-illuminating and requires no batteries, charging, or external light source. It provides visible illumination 24 hours a day for the life of the tritium, which is covered under HiViz's 12-year warranty.

What's the difference between the red front and green rear sight?

The front sight is fiber optic red (bright in daylight) combined with tritium glow for low light. The rear sight is tritium green. This color contrast—red front, green rear—aids rapid target acquisition and sight alignment in varied conditions.

Can I install these myself?

Proper installation requires professional gunsmithing to ensure correct alignment and function. We recommend having these sights installed by a qualified gunsmith.