3M™ PELTOR™ Optime™ II Helmet Attach Earmuff H520P3GS/E, Green, Class 5 SLC80 29dB 3M™ PELTOR™ Optime™ II Earmuffs, H520P3GS/E have been developed for demanding noise-hazard environments. A suitable choice for environments with substantial industrial noise or construction machinery, like airports and agricultural work. Compatible with 3M 25 mm hardhats and visors. Also includes 30 mm hard hat adapter. Reduces noise levels up to 29 dB Large space inside the cups helps minimise heat and moisture build-up Soft, wide, cushions help reduce pressure around the ears Cushions and inserts available as replacement Hygiene Kits