MSA RescueAire II Portable Air Supply System with FireHawk slide-to-connect Mask Mounted Regulator consists of a flame/heat resistant carrying harness with an adjustable Nomex/Kevlar shoulder strap. System with L-30 cylinder contains an Audilarm low pressure warning device, a pressure-reducing regulator, a second-stage mask-mounted regulator, a 36 in Quick-Fill EBS connection and an Extendaire EBS connection.