Thread: Clip on Night Vision

Can anyone help explain the different models of clip on NV that are available on the market?
I see Sytong and Pard are the main two brands but both have lot's of different models that I can't really tell what the differences are.

I hated the idea of adding a butt spacer so thought that a dedicated NV scope would be the way to go, but if I don't need to do that then I like the idea of being able to use a single unit on my 22, 17hmr and 223.

What I do know is:
Can get range finding and non range finding models.
850nm vs 940nm is the wavelength of IR "light" with pros and cons each way
Pard 007A was the original model which needed a butt spacer of some sort to get behind it properly, the 007S is 45mm shorter that you don't need the butt spacer.

How do they Sytong models (HT-66, -77, -88) and the Pard 007SP compare?

I'm leaning towards the Pard 007S at the moment but see 55six has some good pricing on the HT-77 LRF which sounds appealiing but I can't tell if Id need a butt spacer or not.
Any advice would be greatly appreciated.