The Grex 1664 16 Gauge 2-1/2" Finish Nailer is a pneumatic finish nailer built for trim, casing, cabinetry, and general woodworking. This is a finish nailer designed for precision fastening in light wood construction and heavier finish work. Model Number 1664. If you need one air nailer that can cover short trim nails and longer 2-1/2 inch fasteners, this one has the range to do it.

The big selling point here is flexibility. The Grex 1664 drives 16 gauge strip fasteners from 3/4 inch to 2-1/2 inches, which gives it a useful spread for everything from window and door casings to more demanding finish applications. A 100-nail magazine keeps you moving longer between reloads, and the rear-loading design speeds that process up when you do need to refill.

Grex also gave this nail gun the features you actually use on the job instead of loading it with fluff. The depth-of-drive adjustment lets you tune nail set based on material density and finish requirements. That matters when you're bouncing between softer stock, hardwood trim, and prefinished material where too much drive pressure can create extra cleanup. The tool also supports trigger or bump fire operation, so you can work for control or speed depending on the task.

From a build standpoint, this is a practical design. Grex calls out a lightweight aluminum body instead of softer magnesium, along with precision-machined aluminum internal piston, cylinder, and firing valve parts. In plain terms, that means the tool is meant to hold up over time without becoming a boat anchor in your hand. The ergonomic comfort grip helps when you're running a lot of trim in a day, and the durable aluminum magazine is a better choice than a flimsy setup on a tool that will see constant loading cycles.

Jobsite details are covered too. The contact safety includes a no-mar tip to protect finished surfaces, which is a real plus when you're setting casing, base, or cabinet parts that are already close to final finish. The 360 degree adjustable exhaust gives you better control over where the air blows, which makes the tool easier to live with when you're working in tight rooms or along finished walls. Operating pressure is rated at 70 to 100 psi, so it fits into a normal shop or trim compressor setup.

Compatibility is straightforward. This Grex nailer uses 16 gauge strip fasteners in lengths from 3/4 inch to 2-1/2 inches and connects through a 1/4 NPT male plug. It is an air-powered fastening tool, so you will need a compatible compressor and hose setup that can maintain the required pressure range.

Who should buy it? Finish carpenters, remodelers, cabinet installers, millwork shops, and serious DIY users who want one 16 gauge nailer with enough range to handle both lighter trim and more substantial fastening. If your work is mostly detailed finish carpentry and you want adjustability, decent capacity, and a tool built around service life, the Grex 1664 makes a lot of sense.

Grex 1664 16 Gauge 2-1/2" Finish Nailer Gets the Important Stuff Right

This is the kind of pneumatic finish nailer that earns its spot by covering a wide range, giving you depth control, and using materials that make sense for long-term use.

• Who it's for: Trim carpenters, cabinet installers, remodelers, and woodworkers who want one 16 gauge nail gun that can handle both lighter trim and longer finish fasteners.
• Why it stands out: The 3/4 inch to 2-1/2 inch fastener range is useful, the aluminum construction is a smart durability play, and the no-mar tip plus depth adjustment are exactly what you want on finish work.
• Worth knowing: This is an air tool, so you need a compressor setup in the 70 to 100 psi range, and the box contents listed only include the nailer itself.

• What size fasteners does this nailer use? It uses 16 gauge strip fasteners from 3/4 inch to 2-1/2 inches long.
• What air pressure does the Grex 1664 require? The operating pressure range is 70 to 100 psi.
• Does it have adjustable nail depth? Yes. It has depth-of-drive adjustment for setting fastener depth based on the material and finish requirement.
• Can it run in different firing modes? Yes. Product data lists trigger or bump fire operation.