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Ear defenders for safety helmets. Adjustable in height. High flexibility ABS arms and cups. Cups padded with synthetic foam. Can be used on their own or with «VISOR HOLDER» faceshield holder. Suitable for GRANITE, SUPER QUARTZ, QUARTZ, ZIRCON and BASEBALL DIAMOND safety helmets.
Cup & headband: ABS. 
Cushion: Foam & PVC.
EN352-3:2002 Earing protection : for safety helmet  
SNR 24 dB
Standard noise reduction
H 27
High frequency attenuation
M 21
Medium frequency attenuation
L 14
Low frequency attenuation
 
ANSI S3.19-1974 American National Standards Institute   
 
NRR 21 dB
NRR – (Noise Reduction Rating - Noise Reduction Rating)