Milkit is a small Swiss brand and its name derives from its first product: a special Presta valve stem along with an injector that allows tubeless users to check, fill, and top off their tubeless sealant without dismounting their tires.
Their "Booster" is an aluminum pressure bottle, designed to assist the tubeless tire inflation process. It comes in either a one-liter or a smaller, .6-liter size that is reviewed here. Boosters come with a screw-on inflation device that is pressurized with a hand pump up to 160psi (11 BAR) and then used to burst-fill a tubeless tire and seat the beads.
Milkit Booster Details • Aluminum bottle, plastic inflation head • Standard Presta filler valve • Inflates Presta valves only • Handy, push-to-inflate feature • Doubles as a water bottle (fits standard cages) • MSRP: $48 USD (small .6 liter) $50 USD (large 1 liter) Includes bottle, inflation head, screw-on cap and stash bag • This product has been recalled, please Contact: Milkit
Doubles as a water bottle: Because Milkit's Booster canister is only filled with air, it can also be safely used as a water bottle (it fits neatly into standard cages) and it comes with a very Swiss looking screw-on cap for such purposes. The device needs no hoses or flip valves - just push its nozzle onto a Presta valve stem to start filling the tire. MSRP is $48 USD for the small .6 liter Boost and $50 for the one-liter size, a comparable price to alternatives currently on the market.
I have used a number of compact compressed air reservoir bottles with various hoses and valves, and most have done an admiral job of seating tubeless tires. I was interested in the smaller of the two Booster bottles, because of the possibility that it also could be stored in a water bottle cage or a hydration pack and used as a sort of refillable CO2 inflation device. As such, the feather-light aluminum bottle was relatively secure in two different bottle cages: an SKS carbon and a Topeak reinforced plastic model. At close to $50, however, I'd use a Velcro band to secure it in the cage.
Charge the Booster with any floor pump through its top-mounted Presta valve
Back to the nuts and bolts, Milkit's futuristic-looking inflation head is very effective. The bottle is pressurized through a conventional Presta valve, so you should be able to charge it with any cycling hand pump. The small .6-liter cylinder is rated up to 160psi (11BAR) and maxes out in about two dozen strokes of a high-volume floor pump. The push-to activate filler nozzle surprised me by making an airtight seal every time I filled a tire. With no hoses, valves or flip levers to deal with, Milkit's Booster is the most user-friendly stand-alone reservoir system I've used to date.
I was doubtful that the smallish bottle could launch a pesky tire. It did take two tries on a historically difficult rim and tire combination, but the task wasn't any more difficult than it was using my trusty Topeak reservoir pump. As witnessed in the video, however, every other combination that I tried popped on in one very easy trial. This pipsqueak pressure vessel delivers the goods.
Push the valve head onto the wheel's valve stem to instantly charge the tubeless tire.
Check to ensure that the cage's hooked front piece is long enough to secure the bottle. This one isn't.
Did I use the Booster as a water bottle? No. But it could be handy to fill up and bring along the next time I am guiding a ride - someone usually has to plug and remount a reluctant tire. Similarly, Milkit's Booster could do double duty as an inflation device and water storage for adventure riders. Is it more effective than a CO2 cartridge? Yes, and unlike a CO2 cartridge, if you botch your first try, you can air up your Booster and have another go at it.
Milkit's Booster tubeless inflation device is lightweight, simple to use and very effective. If I were using it exclusively at home, I'd spend the extra two dollars and buy the larger-volume one-liter version to give me the upper hand on reluctant tire/rim combinations. As a take-anywhere tool, however, the .6-liter Booster will be hard to beat.—RC
UPDATE— June 11, 2018 As noted in the comments, there have been reports that the Milkit Booster's valve head could have a dangerous defect. An official press release to address the issue and how to proceed is forthcoming from Milkit and we will be linking it here, At this time, customers who have a Milkit Booster should not use the product.
Recall Notice: Milkit has issued an official recall notice which can be read here - and should be considered immediate action for all customers who have purchased or possess the Booster product.