Halcyon Custom Doubles System Seac medics and operators have been

medics and operators have been forced to continually use recreational gear for professional operations

thin panel of foam in the back

the MK7 can now be worn in a diagonal orientation across the chest

Smart Seals system – original

Halcyon Custom Doubles System Seac medics and operators have beenStandard Doubles BC System Built for the depths. Ready for what's next. Halcyon helped shape technical diving from the start, beginning with twin cylinders. As pioneers of the backmount systems, we redefined twin set diving with the Evolve: the first circular dual bladder system, built for perfect balance and trim. The Standard Doubles Cylinder System features the Evolve wing in your chosen lift capacity, with an upgrade option to the advanced Legend