If not using my Peltor 100 muffs, or bulk foam plugs, and I use another Peltor double sided ear plug. One side is green and is like a normal ear plug (indoor use) but the other side is yellow and has a hole so you can hear (for outdoor use).
Headset:
https://www.midwayusa.com/product/863017/peltor-tactical-100-electronic-earmuffs-nrr-22db-black
Foam:
https://www.midwayusa.com/product/2099110047/radians-foam-ear-plugs-nrr-32-db
Double sided ear plugs (this shows different brand, mine had Peltor on the package):
http://www.cabelas.com/product/shooting/shooting-accessories/hearing-protection-enhancement|/pc/104792580/c/104769180/sc/104381280/earshield-duoforce-ear-plugs/1954549.uts?destination=%2Fcatalog%2Fbrowse%2Fhearing-protection-enhancement%2F_%2FN-1100232%2FNs-CATEGORY_SEQ_104381280