Best nut driver set

The Klein 65456 is my top pick because it handles the jobs that stop other nut drivers. Klein says the handle passes through and the shaft is fully hollow, so you can run a hex nut down threaded rod of any length.

That's the point of a pass-through driver. A normal hollow driver works until the rod or bolt hits the bottom of the hollow, and then it stops. Klein says this design prevents that bottoming out, and its spec sheet lists the application as nut driving on unlimited bolt lengths.

Threaded rod is everywhere in plumbing. It holds up pipe hangers and strut. When a nut has to travel a long way up a rod, a pass-through driver keeps you from switching to a wrench halfway.

The second feature is the wrench assist. Klein says the hex shaft is cold-forged steel, so you can put a wrench on it to add torque when a nut won't turn by hand.

Klein calls the shafts and handles reinforced and heavy-duty, built to take the high torque that kind of work needs. The hex is a 6-point design that Klein says maximizes contact with the fastener and cuts the risk of stripping it.

The sizes run 1/4, 5/16, 3/8, 7/16, 1/2 and 9/16 in. That 9/16 in. driver is one the 647 and 631M sets don't have. You give up the 3/16 and 11/32 in. sizes those sets include.

Each driver has an ASME color-coded dome stamp, so you can grab the right size fast. Klein lists 3.5 in. shafts, handles 4.3 to 5 in. long, and 29 oz for the whole set.

Klein's warning is plain: these aren't insulated and won't protect you from electric shock. Wear eye protection, as Klein says.

My call: if you buy one set for plumbing work, buy this one. It was sold by Amazon.com, new and in stock, on the day of the update.

The Klein 647 is the long-reach set. Every driver has a 6 in. (15 cm) shaft, and Klein says the full hollow shaft makes it easier to work on long bolts.

Klein's spec sheet shows how deep that hollow goes. It runs from 7.147 in. on the 1/4 in. driver to 7.567 in. on the 1/2 in. driver. That's the deepest Klein lists for any regular set on this page. Klein lists a depth for the 3/16 in. driver too, so the smallest size is hollow here, unlike the 3/16 in. driver in the 631M.

Klein says this set holds the nut drivers professionals carry most often. The sizes are 3/16, 1/4, 5/16, 11/32, 3/8, 7/16 and 1/2 in., listed by Klein as catalog numbers 646-3/16 through 646-7/16, plus a 630-1/2.

The handles are Klein's patented Cushion-Grip, which Klein says gives more torque and comfort. Inside, flanges anchor the shaft so it resists twisting in the handle.

The shafts are chrome-plated, which Klein says resists corrosion. The set is made in the USA.

Klein lists the whole set at 27.2 oz. The shafts get thicker as the sizes go up, from 0.33 in. on the 3/16 in. driver to 0.718 in. on the 1/2 in.

Shaft diameter matters in a tight spot. A fat shaft can block the next fastener over, so check the space around the screw if you're working in a crowded panel.

These aren't magnetic, so you'll start screws by hand. Klein sells a magnetic version, the 647M, but it showed low stock on Amazon on the day of the update, so I picked the 647.

Klein's warning applies here too: not insulated, and no protection against electric shock.

My call: if your fasteners sit deep, buy this set. It was sold by Amazon.com, new and in stock, on the day of the update.

The Klein 631M is the set I'd keep in the bag for everyday hex screws. The tips are magnetic, using what Klein calls rare-earth magnets, so a screw stays on the driver while you start it.

That's a real help on access panels and covers, where you're holding a panel with one hand and starting a screw with the other. Drop a screw behind a cabinet once and you'll see why magnets matter.

Klein says the set holds the 7 most popular nut driver sizes: 3/16, 1/4, 5/16, 11/32, 3/8, 7/16 and 1/2 in. Those are the same sizes as the 647, on shorter 3 in. shafts.

The shafts are full hollow, Klein says, so they slide over long bolts or studs. There's one exception Klein points out itself: the 3/16 in. driver doesn't have a hollow shaft.

The handles carry Klein's Tip-Ident color coding on the ends. Klein says it helps you spot the right size and line up the hex orientation, even in a tool bag or pouch.

Inside the handle, flanges anchor the shaft against twisting. The grip is the same Klein Cushion-Grip as the 647.

Klein lists the set at 24 oz, 3.2 oz lighter than the long-shaft 647. Klein doesn't list hollow depth for this set, so I can't tell you exactly how long a bolt it clears.

It's made in the USA, and like every Klein set here, it isn't insulated. Klein says it won't protect you from electric shock.

Short shafts are the trade-off. A 3 in. shaft fits where a 6 in. one won't, but it can't reach a fastener sitting deep in a housing. If you work in both kinds of spaces, the 631M and 647 make a good pair.

My call: for everyday hex screws, this is the set. It was sold by Amazon.com, new and in stock, on the day of the update.

The Klein 65160 is the metric set. It holds seven drivers: 5, 5.5, 6, 7, 8, 9 and 10 mm. If you've ever forced an inch driver onto a metric hex head, you know why a real metric set matters.

Klein calls these standard length for most applications, with 3 in. shafts. The shafts are fully hollow and fit over long bolts and studs, per Klein.

Klein's spec sheet gives the hollow depth for each size. It runs from 4.137 in. on the shallowest size to 4.363 in. on the 10 mm. That's more than the 3-3/4 in. on the 32940 power drivers.

Klein says the drivers are heat-treated, tempered steel, and the shafts are fully chrome plated to resist corrosion. It adds that the set meets or exceeds the applicable ASME/ANSI specifications.

Each handle has Klein's Tip-Ident marking, and the handle end is color coded, so you can see the size and line up the hex.

The grip is Cushion-Grip, and Klein says the handles resist slippage. Internal flanges anchor the shaft against twisting.

Klein lists the set at 24 oz, the same as the 631M, and says it's made in the USA. It isn't insulated or magnetic.

The shafts are slim. Klein lists them from 0.373 in. across on the smallest size to 0.57 in. on the 10 mm, so the biggest metric driver is still thinner than the 0.718 in. 1/2 in. driver in the 647.

The range stops at 10 mm, so this set won't fit larger metric hex heads.

My call: if you work on metric hardware even now and then, keep this set next to an inch set. It was sold by Amazon.com, new and in stock, on the day of the update.

The Klein 32940 is a set of power nut drivers. There are no handles. Each one has a 1/4 in. hex drive that goes into an impact driver, and Klein says they're impact-rated.

What sets them apart is the magnet. Klein says the magnet size increases with each hex size, so the bigger fasteners get a stronger hold. It uses rare-earth magnets, which Klein says lets you drive one-handed.

They're also hollow. Klein lists a 3-3/4 in. hollow depth for working on threaded rod. That's shallower than the 647 and 65160 hand sets.

The shafts are 5 in. long. Klein says that gives extended reach into recessed areas. The overall length is 6.3 in.

The sizes are 1/4, 5/16, 3/8, 7/16, 1/2 and 9/16 in., the same range as the 65456. Each one is color coded, and Klein says the finish protects against corrosion.

Klein makes them from high-grade impact steel. The whole set weighs 16 oz, the lightest here, since there are no handles to carry.

Klein's warnings are worth reading. Don't use them to pry or chisel. Never use them on or near live electrical circuits. They aren't insulated.

On a run of strut or a row of hanger nuts, an impact driver with a hollow, magnetic driver saves a lot of wrist turns. That's the job this set is for.

The set has no handles, so it isn't a replacement for a hand set. When a screw needs a light touch, a handled driver gives you more feel than an impact driver.

My call: if you already own an impact driver, add this set to your hand set. It was sold by Amazon.com, new and in stock, on the day of the update.

The Wiha 32296 is the only insulated set on this page. Wiha says every insulated tool it makes is tested one at a time to 10,000 volts AC and rated to 1,000 volts AC, or 1,500 volts DC, for work on energized equipment.

Wiha lists the standards it meets: VDE certification, EN/IEC 60900 for protection against arc flash, ASTM F1505 for insulated hand tools, and CSA. The Amazon listing adds NFPA-70E.

The set has 11 drivers, from 5/32 to 5/8 in. That's the widest range here. It reaches below the 3/16 in. Klein drivers and past the 9/16 in. ones.

Wiha molds the handle directly onto the blade, so the insulation and handle are one permanent piece. The grip is Wiha's SoftFinish cushion grip.

There's a small detail I like. Wiha says the handles have parallel flats to keep them from rolling away when you set one down.

The Amazon listing says the blades are Wiha's CRM-72 tool steel, with precision-machined tips and a deep-drawn 1 in. socket. Wiha doesn't list a hollow depth beyond that, so don't count on these for long bolts.

They're long tools. Wiha's parts list gives 9.3 in. overall for the smallest sizes and 9.6 in. for the rest. The set weighs 3.0 lb, the heaviest here.

It's made in Germany. Wiha backs its tools with a No Hassle Guarantee: return within 12 months and Wiha will repair or replace.

Insulated handles add bulk, and that's the trade for the rating. Check the space around a fastener before you count on fitting a 9.6 in. driver into it.

My call: if you work around wiring at all, this is the set to own. It was sold by Wiha Tools, new and in stock, on the day of the update.