Hi Watchthebear,
Yes the one that clips to the frame of your glasses. I never used the lens type because I find that eye loupes are more versatile. Meaning you can use them just stand alone without the clip on. I think the easiest way to determine this is to buy a couple of the clipon’s , being that they are so affordable and try them for yourself. I think you will be amazed. I really hoped this helped.
I wish you well. 
Jim