What does a thermal clip-on do that a thermal scope doesn't?

It sits in front of your existing day scope and feeds it a thermal image, so you keep your scope, reticle and zero. A dedicated thermal scope replaces the day optic entirely.

Does it hold zero when I take it on and off?

A clip-on is meant to return to zero when remounted on the same rifle and mount, but you should confirm point of impact at the range after each swap. The host scope's own zero is not changed.

How long does the battery last?

Sig Sauer rates runtime at 9+ hours on one 18650 battery. Carry a spare cell for full-day or cold-weather hunts, since cold drains cells faster.

What magnification do I get?

The unit provides 1-8x magnification. The total image you see is that multiplied by your day scope's setting, so a 4x scope at 2x on the clip-on gives 8x overall.

Expect the clip-on unit itself and its mounting hardware. Check the included accessories for your mount type, and supply your own 18650 battery and charger.

Is it compatible with any riflescope?

It works with standard day scopes that have enough front tube to mount the adapter, but the image is only as good as the host scope. Low-power variables with clean glass give the best results.