$20 for one set of earplugs?
Yup it’s an earplug for specific uses.
I use a similar one for truck driving. I never tried it at the shooting range. I planned on using it on a plane.
You must put this thing away in it’s case always after use otherwise you’ll lose it. I lost my first one. Yes I bought a second one.
Just used mine at a few concerts recently. Worked as advertised. Much better than standard earplugs that really just muffle the sound.
You’ll be glad you didn’t - these aren’t rated for that kind of noise attenuation. For taking the edge off live concerts, these work well; for excessive industrial noise or shooting… not so much.
How does one measure the ear?
I have a set of these and swear by them for EDM or metal concerts.
What’s the difference between this and the foam cheap ones, you may ask? Well, if you don’t care about music, go ahead and use the cheap ones. Are they more expensive than foam? Absolutely. Are they worth it? In my book, they definitely are.
These ear plugs contain some kind of magic that reduce the sound volume without muffling out the higher tones. Every time I wear them, the music sounds so good that I have to take them out to make sure they’re working (they always are). They keep the music sounding great without having to shout to my friends all the way home. 
Lots of reading here. LOL
Will they block out your children whining and your husband snoring while you watch TV?
I use these in data centers (hate stuffing marshmallows in my ears) and outside (leaf blower, mower) - carry them everywhere on my keychain.
On airplanes and hotel rooms, I use Bose QC35’s ANC to totally tune out the airplane.
Probably not, but if that’s what you’re looking for, may I suggest this?
Yes, please!
When do you expect these to be the Deal ofthe Day?