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3M Classic Plug: Metal Detectable
311-4101
Polyurethane Foam Earplugs
NRR 33 dB
CSA Class A(L)
More info
Style: Corded
NRR dB: 33
Size: Large
Certification(s): CSA Class AL
Pairs/Box: 200
Implanted stainless steel ball bearing in the earplug and metal particles in the cord
Poly bag keeps each pair of earplugs clean before use
Slow-recovery earplug foam is flame-resistant and water-resistant
CSA Class AL
Test compatible with 3M E-A-Rfit Validation System
NRR dB: 33
Size: Large
Certification(s): CSA Class AL
Pairs/Box: 200
Implanted stainless steel ball bearing in the earplug and metal particles in the cord
Poly bag keeps each pair of earplugs clean before use
Slow-recovery earplug foam is flame-resistant and water-resistant
CSA Class AL
Test compatible with 3M E-A-Rfit Validation System