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Brass 3/8-in Compression Cap Fitting

Ratings & Reviews for ProLine Series Brass 3/8-in Compression Cap Fitting

4.6
252
Review
 4.6 out of 5
253 Reviews


94% Recommend this product

Ratings may include incentivized customer reviews.

What Customers Are Saying

The compression cap appears to be a generally useful and effective product for sealing off water lines, valves, and other plumbing fittings. Many customers found it worked as expected to stop leaks and facilitate home renovation projects, though some noted using a small washer or Teflon tape helped create a tighter seal. While a few had issues with the cap not fitting properly or leaking, the majority reported it as a reliable and versatile solution for various plumbing needs.

Customer review summary generated by AI, including incentivized reviews.
253 Customer Reviews

Useful

Would Recommend

Í found items hard to find somewhere else.

September 22, 2025
Verified Purchaser
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Well-made part! Stopped a water-line leak.

Would Recommend

A very helpful sales associate helped me locate this part. Put it on a refrigerator water line to stop a leak. Worked great!

September 15, 2025
From Brass 1_SLASH_4-in Compression Cap Fitting Verified Purchaser
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Lowes has service.

Would Recommend

I was helped by an interested and alert guy who was in the aisle helping people. Sorry I don't remember his name, a Lowe's employee. I didn’t get this service any where else.

September 5, 2025
Verified Purchaser
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It worked with a minor modification.

Would Recommend

I had to use a separate rubber washer to make it seal, but once I did that it served its purpose until I could get a plumber to fix the leak.

July 18, 2025
Verified Purchaser
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do the job

Would Recommend

bought to seal an unused straddle valve and you need to apply lots of Teflon tape, otherwise it will leak. So far 3 days passed it worked.

July 17, 2025
From Brass 1_SLASH_4-in Compression Cap Fitting Verified Purchaser
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Caps off ice maker supply line

Would Recommend

Works as should, a bit expensive for what it is, but that seems across the board

July 3, 2025
From Brass 1_SLASH_4-in Compression Cap Fitting Verified Purchaser
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Keep on hand!

Would Recommend

Closed off water line to icemaker so whole house doesn't have to be turned off while waiting on parts.

June 18, 2025
From Brass 1_SLASH_4-in Compression Cap Fitting Verified Purchaser
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Keep Turning and its Great

Would Recommend

Used this to cap off a angle stop that both couldn't be desoldiered nor completely shut off. Only thing i will say is keep turning, the seal doesn't seal until it is ratcheted down pretty tight. Im an able bodied 39 year old so it requires some elbow grease.

June 4, 2025
Verified Purchaser
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Works

Would Recommend

Works, does what it needs to, seals off fridge water line that I am no longer using

June 3, 2025
From Brass 1_SLASH_4-in Compression Cap Fitting Verified Purchaser
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quality part

great part works as designed.

May 27, 2025
From Brass 1_SLASH_4-in Compression Cap Fitting Verified Purchaser
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