Hello friends, the case diameter of this men's watch is 46mm

I brought two watch from you and i m going to order another one but i need also one black belt for the last watch , how can i buy only belt ?

If you mean a watch band then you have to see if one option is to buy a watch with a black band. If not, then your screwed because they don't sell separate bands. I know because I asked the company. You would have to buy a separate ' belt ' and put it on the watch yourself. You're Welcome. 2ed

Can this watch come with rubber strap

Hello, we have this men watch, you can change the strap yourself, or go to a professional watch shop to change the strap

How well does this watch glow at night, on its own, without hitting a button? I just want to be able to see the time in the dark.

Not to much unless the watch has been under light and the fluorescent stuff remains charged. Best bet is to press the button. it's a great watch, I love it. 2ed