The concept behind high-pressure air tools is simple: the higher the pressure, the more air that can be compressed into the same space. Max has capitalized on this premise and made air tools smaller and lighter than the competition without sacrificing power.

The HS90 is a 21º full round-head framing nailer with a unique magazine that holds two strips of nails side by side rather than end to end. The short magazine makes the HS90 feel more balanced than other stick nailers, and that balance makes it comfortable to use. Although the HS90 weighs only 5.8 lb., it can easily bury 3 1⁄2-in. framing nails into doubled-up LVLs with little recoil.

Standout features on the nailer include a flip-open trap for easy jam clearing (which I never had reason to use), an aggressive nosepiece for toenailing, and a swiveling hose fitting. An anti-doublefire mechanism and trigger lock make it the safest nailer I’ve used. It’s hard to mention the HS90 without talking about Max’s compatible high-pressure compressor, especially because the gun is useless without it. This 14-in.-wide by 24-in.-long compressor weighs just over 50 lb., so it can easily be carried with one hand. Each pair of outlets—two at 400 psi and two at 120 psi, to run standard nailers— has a separate regulator, and the gauges are flush-mounted, protecting them from damage. The compressor can be used with an extension cord—a plus when several subcontractors are fighting to use the same outlet—and is so quiet that you can stand directly over it and have a conversation without raising your voice.

For all my praise, though, this new stick nailer is only as good as the system as a whole, which I think has two major drawbacks: cost and compatibility. I love the HS90, but I can’t use it without the high-pressure compressor. I run a five-member framing crew, so at any given time, it’s likely (and highly encouraged) that we have five framing nailers operating at once. For the couple of months we tested this system, we ran only three nailers, and although the Max compressor did a great job of keeping up with our air demands, it cycled almost nonstop every day and certainly went home tired. Factor in the compressor’s high price of $1500, and that situation makes me more than a little nervous.

But it’s not just the compressor. If one component in this highpressure system goes down in the middle of the workday, I’m sunk. The HS90 can’t be connected to a conventional air hose, and the 400-psi hoses don’t work with a standard compressor. I can’t borrow somebody’s nailer in a jam, or run to the hardware store for a replacement air fitting or hose splice.

Bottom line: If I needed only one framing nailer and had no other factors to weigh in the decision, the HS90 would be my first choice, hands down. But to me, the system still leaves a bit to be desired before I would consider it a smart trade-off for the bulk and weight issues of typical 120-psi nailers, hoses, and compressors.