How to Use a Bolt Gauge / Thread Checker

A bolt gauge is a fast identification tool for diameter, length and thread, but it does not determine material grade by itself.

Last reviewed 2026-09-10 · reference FG-6544B5 · Report an error on this sheet

How to Use a Bolt Gauge / Thread Checker

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QUICK RULE

A bolt gauge is a fast identification tool for

diameter, length and thread, but it does not determine

material grade by itself.

Pass the shank through the smallest hole it fits

LENGTH (under head)

1. DIAMETER: pass the shank through the gauge hole that fits correctly.

2. THREAD: gently try the threaded checker or use pitch leaves; never force the fastener.

3. LENGTH: align the correct datum with zero - under a protruding head, top of a

flat/countersunk head.

4. HEAD/WRENCH: use across-flats measurement if the gauge includes it.

5. GRADE: read head/nut markings separately.

6. WRITE THE FULL CALL OUT: size-thread x length + product + grade/class + material/finish.

IDENTIFICATION ORDER

Product -> diameter -> thread -> length -> head/drive -> grade/material -> finish -> governing specification

REFERENCE ONLY. Verify the current ASME/SAE/ASTM/ISO/OEM standard and manufacturer data. Do not use as the sole basis for critical fastener selection or installation.

Fastener Guide reference FG-6544B5 · thefastenerapp.com/fastener-guide/measure-and-identify/how-to-use-a-bolt-gauge-thread-checker · © The Fastener App. Reference only — verify the current governing standard, drawing and manufacturer data before specifying or installing.

Scan the label, the item lands in the shopping cart

Your rep or the customer scans a barcode label or they can select items from your store. No part number to remember, no phone call to your counter, no one re-keying anything.

Built into the app, not a separate device or an add-on

Works on any phone camera, or a handheld scanner if they have one

Scans your competitors’ barcode labels too^*

Customers and employees can place orders 24 hours a day, even after hours, and the orders will be waiting for you when you get there in the morning. You can choose to be notified every time an order is placed, whether you’re at the office or not. It gives you greater visibility into your company’s ordering activity.

* Simply cross the number in the system to ours, and we can walk you through the process.

See what every customer buys from you

Every account gets a category chart: share of dollars, share of times ordered and share of pieces. Your reps see what each customer buys from you, and the categories they are buying somewhere else stand out.

Share of dollars

Fasteners37%$69,879

Electrical10%$19,152

Fleet and Automotive7%$12,293

Hardware and Building Supplies5%$10,243

Tools and Equipment5%$9,811

Cutting Tools and Metalworking5%$9,740

Plumbing5%$8,865

All other25%$46,410

Share of times ordered

Fasteners44%355

Electrical12%94

Fleet and Automotive7%53

Tools and Equipment6%48

Cutting Tools and Metalworking4%36

Pneumatics4%34

Hardware and Building Supplies4%33

All other20%162

Share of pieces

Fasteners75%486,316

Fleet and Automotive6%38,905

Electrical5%31,100

Hardware and Building Supplies3%19,775

Sealing3%17,704

Abrasives3%17,251

General MRO2%16,133

All other4%23,770

Sample report from our demo store.

Sales rep territory management

The time planner splits each rep’s month by how much every customer spends. A customer that is 20% of the rep’s business gets about 35 hours a month, about 8 hours a week, and the rep’s week is laid out for them.

Share of the rep’s business

Summit Precast LLC20.2%

Brunswick Galvanizing Inc.14.6%

Talleyrand Signs LLC8.0%

Mayport Tool & Die Inc.7.8%

Eagle Mechanical LLC7.2%

Premier Electric Group5.9%

Tallahassee Packaging LLC3.7%

Coastal Maintenance Group3.3%

All others (64 customers)29.4%

Time each customer deserves

Customer	Hours a month	Hours a week
Summit Precast LLC	35.0	8.1
Brunswick Galvanizing Inc.	25.3	5.8
Talleyrand Signs LLC	13.9	3.2
Mayport Tool & Die Inc.	13.5	3.1
Eagle Mechanical LLC	12.5	2.9
Premier Electric Group	10.2	2.4
Tallahassee Packaging LLC	6.4	1.5
Coastal Maintenance Group	5.7	1.3
All others (64 customers)	51.0	11.8

Sample plan from our demo store: 173 hours a month, all selling time.

Nearly 3,000 real product photographs, covering more than 27,000 SKUs.

We had a professional photographer come in and spend weeks in our warehouse, photographing and producing real, high-resolution photos of many of our products. This work is ongoing, and many more products will be added. Right now the photographs cover more than 27,000 SKUs. We also have AI image generation capabilities.