Commercial hearing protection is rated for different decibels of noise. Get the highest level of protection you can afford. You only have one pair of ears and as someone who has lost a considerable amount of hearing from jets and gunfire in the military, I'm here to tell you once lost, it won't come back.
To protect what hearing I have left, I use the electronic type muffs. They can be set to enhance normal voice and background noise, but instantly block loud noises, such as gunfire. I don't know how they work, but they do work well. On those rare occasions where I find myself shooting at an indoor range, I use foam plugs in addition to the muffs.
Spend a few bux and get the good stuff. Your precious hearing is not a place to go cheap.