Identify the operation
A thin disc is used for cutting, a grinding disc removes more material and a flap disc combines stock removal with finishing.
Compatibility is mandatory
Disc diameter, bore and rated maximum speed must match the grinder. Use a product marked for stainless steel when ferrous contamination must be avoided.
Safety
Keep the guard installed, use the side handle, wear suitable protection and never use a damaged or expired disc.
Important
The stated parameters are starting points. Test progressively on scrap and always respect manufacturer limits.