In The Room (2003), during Johnny's birthday party, Mike can be seen wearing a plastic blue moon watch from a box of Lucky Charms. I'm actually not even kidding seriously what the fucking fuck
Tangentially related: I once met a Polish woman who swore up and down that she had been essentially lured to her financial ruin, sex trafficking/slavery, and near death by Tommy Wiseau.
She claimed he and her met online, he promised to marry her, and he convinced her to get a job on a cruise ship to travel to him, she did so, met him, whereupon she was essentially folded into a harem akin to P Diddy's freakoffs, which she then had to escape.
...
I have no clue if she was completely nuts or not, but I do know she completely believed this.
If you mean the watch face, it seems like it's probably around 40 mm length-wise. The band seems like it can accommodate an adult man's wrist, although Mike here has it toward the very end of his wrist, and we never see what hole he has it in.