55 Pcs Nut and Bolt Thread Checker (25 Metric & 30 Standard), Bolts and Nut Identifier Thread Gauge, Detachable Bolt Size Finder Especially for Tight Spaces

Get a cheap bolt sizer kit on Amazon like this one: https://a.co/d/07oxYx3z There's other kits with more sizes (for more money) so check them out and get what fits your budget