Moogiitools2 inch Caster Wheels Set of 4（Pcs）, Lockable Bearing Plate Caster Wheels with Brakes, 360-degree Swivel Casters

What kind, size of screws do you use to affix them to your project?

Picture is silver description says black which is it? I need black. Also I only need one are these available in a single pack?

Description (and pictures) says 800 lbs capacity for 4 pack of 2in wheels, but the product detail summary says 600 lbs for 4 pack of 2in wheels?

Would these stand up when mounted on a tablesaw cabinet. Tablesaw is cast iron and likely weighs 250-300lbs. I'd prefer lower wheels?