Description
The HexSizer High Heat Heavy Hex Gauge in wallet size measures a heavy hex nut from one flat and tells you the standard nut size, which is also your wrench or socket size. At 2" x 3-3/8", it's the size of a credit card. The inch side reads ASME heavy hex nuts from 1-1/16" to 4-5/8" and studs from 5/8" to 3". The metric side on the back reads nuts from 32 mm to 120 mm and studs from M22 to M76. It works on installed nuts, where the stud is in the way of a caliper or an across-the-flats measurement.
The same HexSizer, sized to ride in your wallet with your cards.
Always on you when the job walk starts
The gauge you left in the truck doesn't help you on a job walk. This one goes in your wallet where the credit cards go, so it's with you every time you badge into the plant. When you get to the flange, heat exchanger or turbine, you pull it out, set the nut into the corner, and read the size from one flat. The stud stays out of the way, and there's no caliper to read in thousandths.
Knowing the size up front means you bring the right hydraulic torque wrench, socket or tensioner the first time. You don't rent the size above and below "just in case," and the crew isn't standing around while somebody drives back to the shop for the right tool.
The nut side is one flat wide and marked with the across-the-flats size of the nut, which is the number you use to pick the wrench or socket. Only standard sizes are marked, so there are no extra tick marks to sort through. The stud side reads like a ruler: put the stud end into the corner and read the stud size. Each size is matched to its nut, so you can go from stud to nut or from nut to stud.
Inch on the front, metric on the back. Both sides measure, and both edges work, so you can check a size from whichever side you can reach.
Made for hot units. 6061 aluminum, anodized and laser engraved. It holds up to a little over 1000°F (538°C), so it won't melt when you're working hot units or live steam lines.
Who uses it: millwrights, bolting technicians, pipefitters and steamfitters in refineries, power plants, chemical plants, pipelines, oil and gas, and wind turbines. It reads studs and stud-bolts from 5/8" to 3" on flanges, valves, pumps, compressors and heat exchangers.
In the package: one wallet-size High Heat Heavy Hex Gauge (inch front, metric back), a detachable tether, and a fitted vinyl sheath.
Over 100,000 HexSizer gauges sold. Made in the USA. U.S. Patent 10,288,400. Designed by Wes Johnson, who has nearly 30 years of experience bolting in refineries, power plants, chemical plants, wind farms, offshore platforms and bridges.
Heavy hex stud and nut size chart (inch)
The wrench or socket size is the nut size across the flats.
| Stud size | Heavy hex nut size (wrench / socket) |
|---|---|
| 5/8" | 1-1/16" |
| 3/4" | 1-1/4" |
| 7/8" | 1-7/16" |
| 1" | 1-5/8" |
| 1-1/8" | 1-13/16" |
| 1-1/4" | 2" |
| 1-3/8" | 2-3/16" |
| 1-1/2" | 2-3/8" |
| 1-5/8" | 2-9/16" |
| 1-3/4" | 2-3/4" |
| 1-7/8" | 2-15/16" |
| 2" | 3-1/8" |
| 2-1/4" | 3-1/2" |
| 2-1/2" | 3-7/8" |
| 2-3/4" | 4-1/4" |
| 3" | 4-5/8" |
Nominal sizes per ASME B18.2.2 heavy hex nuts. For studs over 3" (nuts up to 6-1/8"), see the full-size High Heat Heavy Hex Gauge.
Metric stud and nut size chart (back of the gauge)
| Stud size | Nut size (wrench / socket) |
|---|---|
| M22 | 32 mm |
| M24 | 36 mm |
| M27 | 41 mm |
| M30 | 46 mm |
| M33 | 50 mm |
| M36 | 55 mm |
| M39 | 60 mm |
| M42 | 65 mm |
| M45 | 70 mm |
| M48 | 75 mm |
| M52 | 80 mm |
| M56 | 85 mm |
| M60 | 90 mm |
| M64 | 95 mm |
| M68 | 100 mm |
| M72 | 105 mm |
| M76 | 110 mm |
The nut side also reads 115 and 120 mm nuts. Their studs are larger than the stud side goes.
Metric wrench sizes per DIN 934 plain hex nuts, the sizes hydraulic torque wrenches and stud tensioners are made for. These are not ASME metric heavy hex sizes, which run larger.
Specifications
| Front (inch) | Nuts 1-1/16" to 4-5/8" (16 standard sizes), studs 5/8" to 3" |
| Back (metric) | Nuts 32 mm to 120 mm (19 sizes), studs M22 to M76 (17 sizes) |
| Standards | Inch side: ASME B18.2.2 heavy hex. Metric side: DIN 934 |
| How it measures | Nuts from one flat; studs from the stud end, like a ruler |
| Works on installed nuts | Yes |
| Material | 6061 aluminum, anodized, laser engraved |
| Heat rating | A little over 1000°F / 538°C |
| Color | Navy blue |
| Dimensions | 2" W x 3-3/8" H x 0.040" thick (credit card size) |
| Included | Gauge, detachable tether, vinyl sheath |
| Made in | USA |
| Patent | U.S. 10,288,400 |
Frequently asked questions
Which one do I need: the 4-5/8" wallet gauge or the 6-1/8" gauge?
If the biggest studs you work are 3" or smaller (nuts up to 4-5/8"), the wallet gauge covers you and goes everywhere your wallet goes. If you work larger turbine or heat exchanger studs, up to 4" (nuts up to 6-1/8"), get the 6-1/8" High Heat Heavy Hex Gauge. It fits a shirt pocket.
Will it really fit in my wallet?
Yes. At 2" x 3-3/8" and 0.040" thick, it slides in where the credit cards go.
How do you measure a heavy hex nut that's already installed?
Set the nut into the corner of the gauge and read the size from one flat. You don't have to reach across the flats, so the stud isn't in the way.
Why does my caliper read smaller than the nut's listed size?
Nut sizes are nominal, not exact. ASME B18.2.2 gives each heavy hex nut a minimum and a maximum width across the flats, and the maximum is the size you call it. Nuts come in at or under that size so the standard wrench always fits. A caliper reading a few thousandths under is normal. The HexSizer only marks the standard sizes, so you read the size the nut was made to, not the thousandths.
What if the nut lands between two tick lines?
Go with the larger size. If the nut goes past the smaller size's tick line, the larger tick line is your size.
Can I use it on hot equipment?
Yes. It's anodized, laser-engraved aluminum rated to a little over 1000°F (538°C).
Can I put my company logo on it?
Yes. The wallet size has room for your logo or contact info, which makes it a strong giveaway for tool companies and manufacturer reps. See private-label gauges.
