Klein Tools BLS18 Color Coded Hex Key Set, SAE and Metric, 18-Piece

Both are in the box. The BLS18 is an 18-piece set covering 9 SAE sizes (7/64, 1/8, 9/64, 5/32, 3/16, 7/32, 1/4, 5/16, 3/8 inch) and 9 metric (1.5, 2, 2.5, 3, 4, 5, 6, 8, 10 mm). The two holders interlock so the SAE and metric cases stack together in a bag or truck box instead of floating loose.

No. The BLS18 keys are not insulated and will not protect against electrical shock. They are plain black phosphate coated steel. For work on energized equipment you need a properly insulated 1000V rated tool, not this set. De-energize and verify before using these on any panel or equipment.

That is what the ball ends are for. The BLS18 keys let you drive at an angle up to 25 degrees off the axis of the fastener, which is how you get at a pulley set screw or a coupling bolt with a shaft or housing in the way. Straight on, use the short leg; the ball end is for the awkward approach.

Individual keys run 4.5 to 8.78 inches (11.4 to 22.3 cm) depending on size, and the arms are 30 percent longer than standard. That extra length is what gets you down past a wireway or into a deep enclosure and gives you more leverage on a stubborn set screw. Klein does warn against slipping a pipe over the arm for more torque.

Each key carries a color-coded plastic sleeve, so sizes are identified by color rather than by squinting at a stamped marking. The sleeve also gives you something to grip on a long pull, which matters when you are running a hundred set screws in a day. SAE and metric live in separate interlocking holders, so you are not hunting a 5 mm among the fractional sizes.

The keys are steel, heat-treated and tempered, with a rust resistant black phosphate coating on every key. Heat treating is what keeps the hex corners from rounding over under repeated torque, and the phosphate finish is the practical part for a set that lives in a damp truck box or a mechanical room.

Yes, both. Metric runs down to 1.5 mm and SAE down to 7/64 inch, so the small grub screws on device trim, thermostat covers, and light fixture canopies are covered. At the other end the set tops out at 3/8 inch and 10 mm for larger equipment fasteners.

The holders together measure 9.28 x 3.85 x 1.27 inches (23.6 x 9.8 x 3.2 cm) and the whole set weighs 2.84 lbs. That is a flat, slim profile that drops into a bag pocket or a bucket sleeve rather than a bulky block. The cases are orange, which is easier to spot at the bottom of a bag than black plastic.