Watch back opener for Seiko SNK809

A tool to open the threaded back cover of a Seiko SNK809 watch. It can be a bit snug, so some finishing work with a knife or a chisel can be required. It should work if you really press it in (it shouldn't damage the watch since it's plastic). It has a slot for 6 mm hex key in the back for added leverage and a couple of through holes if the watch really gets stuck and you want to push it out with something.

NOTE: I am not entirely sure if this will work if you have the original cloth strap or