The K2 Backside Float 30 uses the same system as Backcountry Access' Float line of airbag packs. The Backside Float uses a single 150L airbag that deploys from the top of the pack through a breakaway zipper. The size and shape of K2's bag is very similar to the airbags used in the Wary and Mammut RAS series and obviously identical the BCA's. While the K2 Backside Float 30 airbag doesn't offer anything like dual bags for redundancy or a head/neck wrap shape like the Mammut Protection Airbags, this design has still proven equally as effective at keeping the wearer on the surface. The Backside Float offers no redundancy like the ABS packs, but our testers can attest to their durability and were impressed by how much effort it took to put a hole in one with an ice axe. Even after we finally managed to put a hole in it, it still managed to inflate fairly firmly and took more time than we expected to deflate.
Trigger MechanismA cool feature of the K2 Backside Float 30 is that the trigger can be worn in either the left or right shoulder strap, helping widen the range of users. Ski and snowboard tourers can wear the trigger in the shoulder strap so that it makes it easiest to grab with their dominant hand, while snowmobilers can wear it on their right side so they can grab it with their left hand and keep their right hand on the throttle. The trigger mechanism itself is a very simple, but extremely reliable mechanical pull attached directly to the trigger handle.
The K2 Backside Float 30 features one of the more plush suspensions among airbag packs in our review (possibly the most plush). The Backside Float features metal stays to help spread the load, and we think that it has the most comfortable padding all around. The face fabric on the shoulder straps feels really nice, making it even more pleasant if lightly clothed in only a base layer (or less).
Despite the slightly-stiffer-than-average frame, our testers were impressed with the downhill performance of the Backside Float 30 and thought it was above average among packs in our review. We also thought it moved with us while skiing or snowboarding better than nearly all the other 30L and larger packs.
The K2 Backside Float 30 is a very heavily featured pack offering a lot of small zippered pockets, including a fleece lined goggle pocket on one side that can be accessed without removing the pack. Our testers liked the snow safety gear pocket which is larger than average and fits most medium and larger sized probes and shovels while still leaving room for potentially wet skins. This "wet room" helps the user keep the contents of the main compartment to stay dry. The Backside Float 30's snow safety gear pocket zips open 2/3 of the way around, similar to the Back Country Access Float 42. This was fine, but we like the complete U-shape opening of the BCA Float 22 and 32 slightly better. We did like the Backside Float 30's "wet room" pocket better than the similarly priced Mammut Ride RAS packs, which were noticeably smaller.
Our testers really liked the two convenient zippered waistbelt pockets and found them big enough for small items like bars, an Inclinometer, or a smaller point-and-shoot camera. We also liked the low profile and tram friendly ice axe holder that keeps both the spike and the pick completely covered. Or conversely, for longer axes, there is a hole in the bottom of the snow safety gear pocket for the spike to stick out the bottom of so it can be carried inside the pack. We found the removable mesh helmet sleeve super functional and it fit every helmet we tried, from low profile climbing helmets to proper snowmobile helmets.
Carrying Skis or a SnowboardThe K2 Backside Float 30 is one of only a handful of airbag packs that is designed really nicely to carry skis, or a split-board split vertically or diagonally, or a traditional snowboard vertically. The ability to carry your skis or split-board A-frame style is nice for long approaches because it tends to sway around less, but K2 and all other manufacturers don't recommend it while traveling in avalanche terrain because of the possibility that it might interfere with deployment.
At 7 lbs 14 ounces (including a full canister) the K2 Backside Float 32 is the heaviest airbag pack in our review, just barely weighing in heavier than the similar volume Black Diamond Halo 28 (7 lbs 8 ounces) or the Black Diamond Saga 40 (7 lbs 11 oz). Unfortunately, it's 13 ounces heavier than its closely designed cousin the Backcountry Access Float 32, which tips the scales at 7 lbs 1 ounce.
Airbag pack costs can sometimes be confusing or misleading because some manufacturers include the cartridge in the price and some don't, while others may or may not include the actual airbag system. K2 Backside Float 30 breakdown: the back with the airbag is $600, and the canister (which is sold separately unless specifically labeled) goes for $175, for a total price of $775. If you already own a BCA pack (or are thinking about getting one), the canister is 100% interchangeable.
