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06MFS-04MFS STRAIGHT

Description & Features

A straight hydraulic adapter from Brennan Industries, this fitting connects a 3/8 inch male flareless seat (06MFS) end to a 1/4 inch male flareless seat (04MFS) end, making it suitable for reducing between two different line sizes in a single inline connection. The 06MFS-04MFS Straight carries an 11/16-16 thread on the larger end and a 9/16-18 thread on the smaller end, with corresponding drill sizes of 0.264 and 0.172 inches respectively.

With an overall face-to-face length of 1.17 inches and a 0.750 inch hex, the fitting is compact and straightforward to install with standard tooling. It is part of Brennan's FS2403 series and is well suited for hydraulic line assemblies where a straight-through, cross-size flareless connection is required.

SKU: FS2403-06-04

Supplier Part Number (MPN): FS2403-06-04

Alternate Part Numbers: AFF2000T0604S, C1ED19, FF2403-06-04

Specifications

Brand Brennan Industries Inc	Brand Brennan Industries	Pack Size 1.00	UOM EA	Supplier Part Number FS2403-06-04	Product Weight 0.10 lbs

Product Questions & Answers (3)

Question by: Lynn H on Jul 18, 2025, 2:47 PM

trying to step down from a 3/8 line to a 1/4 line, is this the right straight adapter for that?

Answer by: Customer Support on Jul 20, 2025, 6:58 AM

For reducing in a straight run, it connects a 3/8 inch male flareless seat end (06MFS) to a 1/4 inch male flareless seat end (04MFS), so it is meant for that 3/8 to 1/4 step-down in one inline fitting.

Question by: Donna H on Apr 3, 2026, 11:34 AM

trying to reduce from 3/8 line down to 1/4 in a tight spot, will this fitting work inline without needing extra adapters or couplings?

Answer by: Customer Support on Apr 5, 2026, 10:38 AM

For a straight inline reduction between a 3/8 flareless seat and a 1/4 flareless seat, this is exactly the fitting for that job. The larger end threads at 11/16-16 and the smaller end at 9/16-18, so it handles both connections in a single piece. At 1.17 inches face-to-face, it keeps things compact, and the 0.750 inch hex means you can torque it down with standard wrenches without any trouble.

Question by: Terry E on Aug 13, 2025, 8:39 AM

So this fitting goes from 3/8 to 1/4? Just want to make sure I'm reading it right.

Answer by: Customer Support on Aug 14, 2025, 11:00 AM

That's correct. This straight adapter connects a 3/8-inch male flareless seat to a 1/4-inch male flareless seat.