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Nylo-Seal Fittings 259-N 04

$0.60/Piece
Part# 259-N04
Tube ODADPart Number
1/40.3750.125259-N04

Overview

Nylo-Seal tube fittings are exceptionally strong. The bodies, made of nylon, are stronger than machined fittings of similar composition. They are furnished complete with nut/sleeve assemblies, made of acetal copolymer. Since the sleeve snaps into and is retained by the nut there is no fumbling for a loose sleeve. Just insert tube into the fitting and tighten the nut 2 to 2-1/2 full turns. Note: The most frequently used combination of tube and pipe sizes are 1/4" Tube x 1/8" Pipe and 3/8" Tube x1/4" Pipe.

For Nylo-Seal tubing, see "Accessories" tab

Less 10% on 50 pieces per size, Less 20% on 100 pieces per size
   
California Prop 65 Warning Symbol

WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov.

Reference Chart

259-P CAP,
259-N Insert (Nylon)

261-N Nut and
Sleeve Assembly

Tube O.D. A D
1/4 3/8 1/8
3/8 7/16 13/64
Tube O.D. Thd. A C
1/4 7/16-20 15/32 9/16
3/8 5/8-20 37/64 3/4

262-N Union

Tube O.D. A B C D E
1/4 1-25/64 63/64 5/8 7/32 15/32
3/8 1-21/32 1-1/4 13/16 23/64 19/32

264-N Union Tee

Tube O.D. A B D E
1/4 1-9/64 47/64 7/32 15/32
3/8 1-11/64 31/31 11/32 19/32

266-N Female Connector

Tube O.D. Pipe Thread A B C D E
1/4 1/8 1-9/64 15/16 9/16 7/32 9/16
1/4 1/4 1-5/16 1-7/64 11/16 7/32 47/64
3/8 1/4 1-27/64 1-7/32 11/16 11/32 3/4
3/8 3/8 1-27/64 1-7/32 13/16 11/32 3/4

265-N Elbow Union

Tube O.D. A B D E
1/4 1-1/64 13/16 7/32 3/8
3/8 1-5/32 15/16 11/32 7/16

268-N Male Connector

Tube O.D. Pipe Thd. A B C D E
1/4 1/8 1-13/64 1 5/8 15/64 15/32
1/4 1/4 1-25/64 1-3/16 5/8 15/64 11/16
3/8 1/4 1-17/32 1-21/64 13/16 5/16 19/32
3/8 3/8 1-19/32 1-25/64 13/16 11/32 19/32

269-N Male Elbow

Tube O.D. Pipe Thd. A B D E F
1/4 1/8 1-1/64 13/16 7/32 3/8 27/32
1/4 1/4 1-1/64 13/16 13/32 3/8 1-1/32
3/8 1/4 1-9/64 15/16 5/16 7/16 1-1/32
3/8 3/8 1-9/64 15/16 11/32 7/16 1-3/32

271-N Male Run Tee

Tube O.D. Pipe Thd. A B D E F
1/4 1/8 59/64 21/32 7/32 15/32 3/4
1/4 1/4 59/64 13/32 7/32 15/32 29/32
3/8 1/4 1-5/32 61/64 5/16 19/32 1-1/16
3/8 3/8 1-3/16 61/64 23/64 19/32 1-7/64

272-N Male Branch Tee

Tube O.D. Pipe Thd. A B D E F
1/4 1/8 15/16 47/64 7/32 15/32 3/4
1/4 1/4 15/16 47/64 7/32 15/32 13/16
3/8 1/4 1-11/64 31/32 5/16 19/32 1-1/16
3/8 3/8 1-11/64 31/32 23/64 19/32 1-7/64

282-N Bulkhead Union

Tube O.D. Pipe Thd. A B C D E F G
1/4 7/16-20 1-57/64 1-31/64 5/8 7/32 15/32 5/8 5/16
3/8 5/8-20 2-1/4 1-53/64 13/16 11/32 19/32 7/8 3/8
*Use 259N inserts w/all Poly-Flo tubing connections. Not needed w/ Nylo-Seal tubing.
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Reviews

exactly as advertised

Ali S Verified Purchase

Nylo-Seal Fittings 259-N 04

November 12, 2024

Perfect fit, problem solved.

Gary A Verified Purchase

Nylo-Seal Fittings 259-N 04

September 26, 2024

Would have worked fine, Just don’t lose the bag in the hangar! Thanks Central Florida Avionics for supplying us with a few!

Kevin T Verified Purchase

Nylo-Seal Fittings 259-N 04

June 28, 2024

Ted L Verified Purchase

Nylo-Seal Fittings 259-N 04

March 18, 2024

Brad L Verified Purchase

Nylo-Seal Fittings 259-N 04

January 26, 2024

FYI. These are a must have on the end of tubing at every fitting.

Robert S Verified Purchase

Nylo-Seal Fittings 259-N 04

October 1, 2023

Julicher A Verified Purchase

Nylo-Seal Fittings 259-N 04

May 6, 2023

Good part. Thx

Robert A Verified Purchase

Nylo-Seal Fittings 259-N 04

April 22, 2023

works good, lasts a long time!

Kell A Verified Purchase

Nylo-Seal Fittings 259-N 04

March 21, 2023

Great

Steven B Verified Purchase

Nylo-Seal Fittings 259-N 04

December 2, 2022

Q&A

Please note, Aircraft Spruce's personnel are not certified aircraft mechanics and can only provide general support and ideas, which should not be relied upon or implemented in lieu of consulting an A&P or other qualified technician. Aircraft Spruce assumes no responsibility or liability for any issue or problem which may arise from any repair, modification or other work done from this knowledge base. Any product eligibility information provided here is based on general application guides and we recommend always referring to your specific aircraft parts manual, the parts manufacturer or consulting with a qualified mechanic.

Q: In Nylo Seal Fittings, is the first fraction in the size column the pipe size or tube size? Example: 1/4 x 3/8

The first number in the size column refers to the tube OD, second number is the pipe thread. In your example, 1/4 tube OD x 3/8 pipe thread.

Q: Please tell me how to assemble when using a cap 259-P.

You would install a cap in a fitting where you would want to cap off the flow. Place the cap in the fitting and tighten the nut down.

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