Here's what other sites are saying:
The ABS Activation Unit includes the compressed nitrogen canister and the trigger needed for the ABS Vario Avalanche Airbag Base Unit to work. Steel cartridge for durability; North America DOT and TC certified. Burst pressure of at least 675 bar. Note: a $30 hazardous materials shipping charge will be added at checkout for shipping pressurized canister. Once you have a cartridge you can exchange it for $45 at Tahoe Mountain Sports. The essential component for the ABS ski airbag system. Burst pressure: 675 bar minimum. Filled weight: 585 g. Refillable
- Tahoe Mountain Sports
An ABS avalanche airbag is an awesome thing to have, but can only be deployed once without needing replacement parts; keep your ABS airbag pack ready to use and always have a spare Activation Unit on hand. This package consists of a canister of compressed nitrogen--which is used to inflate the bags because it resists icing at low temperatures--and a trigger that activates the canister. Once you've used your existing canister and trigger, both must be replaced or refilled, which must be done by a certified ABS refiller.
The ABS Activation Unit compressed air cylinder works with the Vario Avalanche Airbag Pack base unit to rapidly inflate the airbag and help keep you at or near the snow's surface during an avalanche.
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