Overview

The 1/4 to 3/8 hydraulic nipple is a single wire hydraulic hex nipple that steps from a 1/4 inch male NPT thread up to a 3/8 inch male NPT thread. It is the compact connector used where a hydraulic or pressure washer line has to change thread size, letting a 1/4 inch port feed a 3/8 inch line or the other way around without an adaptor stack.

The listing gives two material options: zinc plated steel for general purpose hydraulic and pneumatic work, and 304 stainless steel for environments that need higher corrosion resistance. The NPT tapered thread seals as it tightens, and the hexagonal body gives a wrench flat for secure tightening. The listing rates the G thread versions to up to 400 bar, which is 5800 psi.

Key Features

• Steps from 1/4 inch male NPT to 3/8 inch male NPT
• Zinc plated steel or 304 stainless steel options
• NPT tapered thread for a self sealing joint
• 3/4 inch hex across flats for wrench tightening
• Rated to up to 400 bar (5800 psi) on G thread versions
• Compact single wire hydraulic hex nipple

Specifications

• Thread 1: 1/4 inch male NPT
• Thread 2: 3/8 inch male NPT
• Material options: zinc plated steel, 304 stainless steel
• Pressure rating: up to 400 bar (5800 psi) on G thread versions
• Seal: NPT tapered thread
• Hex body: 3/4 inch across flats

Applications

• Hydraulic hoses and test points
• Pressure washer adaptor fittings
• Pneumatic tool connections
• Workshop fluid systems
• Industrial and agricultural equipment setups

What You Need to Complete the Job

Pair the nipple with a 1/4 inch stainless steel coupling for a clean quick connect setup, and a 1/4 inch quick connect plug where the line needs a sealed end. Run it in a 40 metre pressure washer hose line, and see the Pressure Washers Accessories range for the rest of the kit.

Frequently Asked Questions

Which thread does it convert?

It steps from a 1/4 inch male NPT thread to a 3/8 inch male NPT thread. The NPT taper seals as it tightens, so the joint is self sealing when the two sides are drawn up together.

What is the pressure rating?

The listing rates the G thread versions to up to 400 bar, which is 5800 psi. For the NPT versions the rating follows the NPT standard, and the tapered thread gives a high performance seal under pressure.

What materials are available?

Two options are listed: zinc plated steel for general purpose hydraulic and pneumatic systems, and 304 stainless steel for environments that need higher corrosion resistance. Choose stainless where the fitting sits in wet or chemical heavy conditions.