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(S66-6-4) COMP/FEM CONN 3/8X1/4

Brand Midland Industries	Brand Midland Industries	Pack Size 1.00	UOM EA	Supplier Part Number 18153	Product Weight 0.09 lbs

Product Questions & Answers 2

Product Questions & Answers

fitting's compression end, does it need any kind of sealant or thread tape on that side, or does it grip the tubing on its own?

Question by: Roy J on Dec 6, 2025, 9:53 PM

Compression fittings like this one work by gripping the tubing mechanically when you tighten the nut. No solder, no flaring, no tape on the compression side. The ferrule seats against the tubing and forms the seal through that mechanical bite. The female threaded end is a different story, depending on the mating fitting and the fluid being run, thread sealant on that side is generally a good idea.

Answer by: Customer Support on Dec 8, 2025, 10:22 AM

got a 3/8 inch tube line and need to hook into a 1/4 female thread port. is that what this fitting is for

Question by: Dwayne H on Feb 13, 2026, 5:18 PM

Made to bridge those two ends, it transitions from a 3/8 inch compression connection on the tubing side over to a 1/4 inch female threaded connection on the other side.

Answer by: Customer Support on Feb 15, 2026, 10:29 AM