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Stainless Steel Duolok Tube Fitting, 0.25 Inch Tube OD Nut

Description & Features

Duolok tube fittings offer a reliable leak-proof connection in instrumentation and process tubing systems. Crafted from type 316 stainless steel these fittings ensure durability and long-lasting performance. The double ferrule design compensates for variations in tubing materials hardness and tube wall thickness providing secure connections across diverse applications.

Manufactured to be gaugeable Duolok fittings guarantee sufficient pull-up during initial installation ensuring ease of use and reliability. Additionally theyre designed for total interchangeability with Swagelok tube fittings meeting rigorous quality control standards.

Straight fittings are machined from cold-finished bar stock according to ASTM A-276 and ASTM A-479 while shaped bodies use close-grained 316 stainless steel forgings per ASTM A-182. Heat code traceability and certified material test reports (CMTRs) are available for all components.

Generally these tube fittings are rated for pressures equal to the maximum allowable working pressures of recommended stainless steel tubing. Elevated temperatures may reduce the systems maximum working pressure capability. For specific applications at elevated temperatures please call for assistance.

Refer to the safety information regarding proper selection of tubing and tube fittings.

Supplier Part Number: ISSD4N

MPN: C1FP15

Specifications

Brand Ssp Fittings Corp	Brand SSP Fittings Corp	Pack Size 1.00	UOM EA	G 0.56	L 0.50	Supplier Part Number ISSD4N	T 0.25	Alternate Part Numbers Alternate Part Number C1FP15, Alternate Part Number MI-08750225, Alternate Part Number MINO-00766X89716, Alternate Part Number SS-402-1	Product Weight 0.03 lbs

Similar Products

Model Number	T	G	L	Price	Action
ISSD4N Stainless Steel Duolok Nut	0.25	0.5625	0.5
ISSD6N Stainless Steel Duolok Nut	0.38	0.6875	0.56

Product Questions & Answers (2)

Question by: Earl H on Jan 7, 2026, 9:10 PM

these swap out direct with Swagelok nuts, right? got a line already running Swagelok fittings and just need to replace a nut on a 1/4 inch tube connection

Answer by: Customer Support on Jan 9, 2026, 6:04 AM

Full interchangeability with Swagelok tube fittings is built into the Duolok design, so swapping in this nut on an existing Swagelok setup is exactly what it's made for. The 0.25 inch tube OD size lines up for quarter-inch tubing connections, and the double ferrule system works the same way you're already used to. No reworking the fitting body or ferrules already in place.

Question by: Floyd R on Nov 15, 2025, 11:46 AM

Will this nut work with a standard Swagelok fitting of the same size?

Answer by: Customer Support on Nov 16, 2025, 3:29 PM

Because Duolok fittings are designed to be interchangeable with Swagelok fittings, this nut should work just fine with a Swagelok fitting of the same size.