Hollis - H-O2 DIN First Stage The counter lungs connect directly

The counter lungs connect directly to the scrubber canister

however it can be uncomfortable when used as an attachment for a scooter with the thrust of the CUDA

however some divers prefer for added weight or stability

A stainless steel retainer locks the lenses in place and provides added strength to the nose bridge area of the mask

Hollis - H-O2 DIN First Stage The counter lungs connect directlyWith the Bulletproof Design of the Hollis HP5 Non Balanced Flow By Piston First Stage the HO2 First Stage is Certified for up to 100% Oxygen Service thanks to Highly Specialized Component Materials and Manufacturing Processes. Cleaned and Assembled in a Clean Room Environment with Specially Designed Materials, Halocarbon Based Lubricants and Color Coded for Easy Identification. The Flow By Piston Design is the only true Fail Safe First Stage Design on