Name: ProLine Series Brass 3/8-in Male x 3/8-in Male Union Fitting
Brand: ProLine Series
SKU: 1000506223
Price: 4.4 USD
Availability: InStock
Rating: 4.9 (49 reviews)

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Unions connect two lengths of tubing together, further lengthening the plumbing line. Constructed of lead-free brass, brass flare fittings are ideal for gasoline, grease, natural gas, and refrigeration/ac applications. The brass construction makes this fitting corrosion-resistant and is able to be used indoors and outdoors. Flare fittings can be used in conjunction with aluminum tubing, brass pipe, copper tubing & steel hydraulic tubing.

Links two lengths of tubing into one continuous line
Constructed of durable, lead-free brass
Brass is corrosion-resistant and can be used indoors and outdoors
Applications include gasoline, grease, natural gas, refrigeration and AC
Compatible with aluminum tubing, brass pipe, copper tubing & steel hydraulic tubing
Do not use Teflon or pipe dope

General
Color/Finish Family	Gold	Maximum Working Temperature (Fahrenheit)	212
Type	Union	Fitting Type	Threaded
Connection Type (End 2)	Male	Sub Type	Male adapter
Connection Type (End 1)	Male	Package Quantity	1
Material	Brass

Dimensions
Diameter (End 2)	3/8-in	Diameter (End 1)	3/8-in

Features
Minimum Working Temperature (Fahrenheit)	32

Certifications
CA Residents: Prop 65 Warning(s)	Prop 65 WARNING(S) -	Complies with Federal Lead Guidelines	Yes
Safety Listing	IAPMO safety listing

Warranty
Warranty	1-year limited

Compatibility
For Use with RVs	No

Miscellaneous
UNSPSC	40171700

Check out the Best Selling Brass Fittings on Lowes.com

Review

4.9 out of 5

49 Reviews

2 Star

1 Star

100% Recommend this product

Ratings may include incentivized customer reviews.

49 Customer Reviews

Sort By

It's made well

Would Recommend

Does what it's made for.

Miracle SoilSeptember 30, 2026
From Brass 1_SLASH_2-in Male x 1_SLASH_2-in Male Union Fitting Verified Purchaser

Was this Review Helpful ?

Easy peezee to install

Bought a new gas grill regulator with hose 2 weeks ago. Working wonderful in fact yesterday made some outstanding BBQ ribs

beerman609September 15, 2026
Verified Purchaser

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Availability

Would Recommend

I bent the split system copper line during install. Luckily, I have experience in flaring lines. A life saver I say.

JawnnieJuly 17, 2026
Verified Purchaser

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It did its job

Would Recommend

It's a flare union, it did its job

DaveJune 13, 2026
Verified Purchaser

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Repair

Would Recommend

Met my need

Mike1952May 29, 2026
From Brass 1_SLASH_2-in Male x 1_SLASH_2-in Male Union Fitting Verified Purchaser

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3 Questions

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How are these things measured? I have one whose outer thread diameter is 5/8", but it's classified as a 3/8", but neither is the inside 3/8". Why?

Could B&K 3/8 in Threaded male Union be used for a LPG application outside? Exposuure to rain, snow, and humidity?

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COMPARE PRODUCTS

		Name	Current Item ProLine SeriesBrass 3/8-in Male x 3/8-in Male Union Fitting
		Ratings	49
		Diameter (End 1)	3/8-in
		Type	Union
		Fitting Type	Threaded
ProLine Series3/8-in x 3/8-in Threaded Male Adapter Nipple Fitting	ProLine SeriesBrass 3/8-in Flare x 3/8-in MIP Union Fitting	ProLine Series3/8-in x 1/2-in Threaded Flare X Mip Adapter Union Fitting	ProLine Series3/8-in x 3/8-in Compression Adapter Fitting	ProLine SeriesBrass 3/8-in Female x 3/8-in Female Union Fitting	ProLine SeriesBrass 1/2-in Flare x 1/2-in MIP Union Fitting	ProLine SeriesBrass 1/2-in Flare x 3/8-in MIP Union Fitting	ProLine SeriesBrass 3/8-in Female Nut Fitting	ProLine Series3/8-in x 3/8-in Threaded Flare X Fip Adapter Coupling Fitting
353	143	31	5	166	143	143	14	100
3/8-in	3/8-in	3/8-in	3/8-in	3/8-in	1/2-in	1/2-in	3/8-in	3/8-in
Nipple	Union	Union	Adapter	Union	Union	Union	Nut	Coupling
Threaded	Threaded	Threaded	Compression	Compression	Threaded	Threaded	Flare	Threaded