Ear protection like this is simply a foam-insulated cup that protects your eardrum from loud sounds that can damage hearing. Some ear protection is specific to particular fields, where there may be known risks of certain frequencies or elevated sound pressures, but for general use, whatever you find in the hardware store will do.

Note that prolonged sound at certain pressure levels can cause damage to hearing, even if short bursts do not. For example, you may not need hearing protection to run a drill for a few seconds at a time, but long periods of drilling can, at least temporarily, damage hearing, due to the frequencies of the sounds drills can produce at certain speeds.

If you're not sure whether hearing protection is necessary, use it anyway. It's always better safe than sorry.

Standard hardware store hearing protection.