Thread Identification Kit

Thread Identification Kit (Thread Test Plug Set)

This thread identification kit is specifically designed for identifying thread specifications in hydraulic fittings, hose fittings, and mechanical connections.

The kit contains a variety of standard thread test plugs, covering common specifications such as Metric, BSP (British Standard Pipe), and UNF/UNC (Unified National) threads, enabling users to quickly and accurately determine the size and type of unknown threads. It is an essential tool for hydraulic fitting selection, maintenance, and repair.

No calipers or complex measuring tools are required—simply screw in the appropriate plug to complete the identification process.

Thread Identification Kit Specifications

Thread Inner and Outer Diameter Reference Table
Metric			Metric			American
	I.D	O.D		I.D	O.D		I.D	O.D
M10×1.5	8.37	10	M36×1.5	34.37	36	2×11 TPI	56.656	59.614
M12×1.25	10.625	12	M36×2	33.8	36	3/8×18 TPI(NPT)	14.95	16.66
M12×1.5	10.35	12	M39×1.5	37.37	39	7/16×20 TPI	9.74	11.1
M14x1	12.91	14	M39×2	36.8	39	1/2×20 TPI	11.33	12.7
M14×1.5	12.35	14	M42×2	39.8	42	9/16×18 TPI	12.76	14.28
M16×1	14.91	16	M45×2	42.8	45	5/8×18 TPI	14.35	15.81
M16×1.5	14.35	16	M48×2	45.83	48	11/16×16 TPI	15.80	17.46
M18×1.5	16.35	18	M52×2	49.8	52	34×16 TPI	17.33	19.05
M20×1.5	18.35	20	M60×2	58	60	13/16×16 TPI	18.923	20.599
M22×15	20.35	22	M64×2	62	64	7/8×14threads	20.56	22.2
M22×2	19.83	22	M64×2	62	64	1×14 TPI	23.29	25.4
M24X1.5	22.35	24	British			1.1/16×12threads	24.7	26.98
M424×2	21.83	24	1/4×19threads	11.445	13.157	1.3/16×12threads	28.04	30.16
M26×1.5	24.35	26	3/8×19threads	14.95	16.662	1.5/16×12threads	31.05	33.33
M27×1.5	25.35	27	1/2×14threads	18.631	20.955	1.7/16×12threads	34.39	36.51
M27×2	24.8	27	5/8×14threads	20.587	22.911	1.5/8×12threads	38.98	41.27
M30×1.5	28.35	30	3/4×14threads	24.117	26.441	1.11/16×12threads	40.74	42.86
M30×2	27.8	30	1×11threads	30.291	33.249	1.7/8×12threads	45.33	47.22
M30×1.5	28.35	30	1.1/4×11threads	38.952	41.910	2×12threads	48.514	50.754
M30×2	27.8	30	1.1/2×11threads	44.845	47.803	Note: Inner and outer diameters are in mm.
M33×1.5	31.37	33	1.1/2×11threads	44.845	47.803	Note: Inner and outer diameters are in mm.

Product Features

1️⃣ Comprehensive Standard Coverage
Metric Threads: M6 – M52, etc.
BSP Threads: G1/8, G1/4, G1/2, etc.
American Threads: UNF / UNC
Meets the requirements of global hydraulic systems.

2️⃣ Clear, Legible Markings
Each plug is engraved with its specific size (e.g., M22×1.5, G1/2, UNF 7/16-20).
Wear-resistant and fade-proof, ensuring markings remain clear even after prolonged use.

3️⃣ High-Precision Machining
Features high-precision thread machining.
Ensures accurate matching and prevents misidentification.

4️⃣ Robust and Durable
Manufactured from high-quality steel (Carbon Steel / Stainless Steel).
Wear-resistant and corrosion-proof, making it suitable for use in industrial environments.

5️⃣ Includes Storage Case
Comes with a high-strength plastic tool case.
Internally partitioned by size for neat, organized storage, facilitating easy portability and management.

Thread Identification KitUsage Instructions

Select a test head marked with a specific size and gently screw it into the internal bore of the connector you wish to test. Continue this process until you identify the correct test head. The proper criterion for a correct match is the ability to screw it in smoothly and effortlessly for at least 2–3 turns without any looseness or play; this indicates that the thread size and profile are compatible. By referencing the size marking on the test head, you can then determine the dimensions of the thread.

The following scenarios indicate a mismatch:
Jams immediately upon insertion → Incorrect thread profile (e.g., Metric vs. UNF)

Feels very loose → Incorrect thread pitch

Screws in only slightly → Mismatched diameter

Applications

This thread test kit is widely used in:

Hydraulic hose and fittings industry
Machinery maintenance and repair
Automotive and heavy equipment service
Oil & gas and construction industries
Workshop and warehouse thread identification

About Tom

Tom is a professional manufacturer and global supplier of hydraulic hoses, fittings, and related accessories. With years of industry experience, we provide complete fluid transfer solutions for a wide range of applications, including construction machinery, mining, agriculture, automotive, and industrial systems.

Our product range covers:

Hydraulic hoses (SAE / EN standards)
Hydraulic fittings (Metric, BSP, JIC, ORFS, etc.)
Hose assemblies and accessories
Thread identification tools and hose machine

With our own manufacturing facilities, Strongflex ensures strict quality control from raw materials to finished products. All products are carefully inspected to meet international standards and customer requirements.

We export to more than 40 countries and actively participate in international exhibitions, building long-term partnerships with customers worldwide.

If you have requirements for products facilitating hydraulic fluid transmission, please feel free to contact us; we can manufacture both standard and customized products to meet your specific needs.