Forespar MF 839 Vented Loop - 1-1/4" - 903011

Marsoni

M251S

$34.99

Get it in 3 business days with 1 day shipping. Friday, May 29

Forespar MF 839 Vented Loop - 1-1/4" - 903011MF 839 Vented Loop 1 1 4" Installing one of our vented loops will ensure that fluids will not siphon from tank to tank. Vented loops are commonly used in the marine toilet system and engine cooling system. The simple valve system incorporated in the top of the loop allows air to enter the line when not in use, yet effectively seals as water or other fluid passes through. Molded in Marelon, neither vent nor loop will corrode. The duckbill one way valve

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I purchased these to wear inside lowcut slip on casual shoes, I don't particularly like to not wear socks in my shoes for hygienic reasons. Prior to purchasing these socks, all I could find were those made of very light beige hosiery type material , and my slip on shoes would slide around a bit. These are light weight and breathable athletic type material, with a very good gripper strip at the heel. One pair of my slip on casual shoes have a particularly lower cut in the toe area, but the shoe is black and I chose the black color and though I see a hint of the sock there, it matches and does not detract from the look of the casual solid black shoe

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Reviewed in the United States on May 15, 2026

Verified Purchase

Anna Wylda

Pawtucket, US

★★★★★ 5

They stay out! No more sock wads!

Size: Medium, Color: (100) White / White / Mod Gray

Best no show socks ever made!!!!! I've been struggling for 2 years to find ones that actually stay on your foot, even other national brands, and I just became content wearing my sneakers without socks. They ALWAYS slid down into my show & I ended up walking on a wad of sock until I could fix it...or usually just took them off after a couple of tries. Enter Under Armor!!! They a mid weight, but not very thick & still breathable. They work too by actually staying on your foot! Not once have they slid down into my show!! Very comfortable but they could be a little more affordable.

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Reviewed in the United States on August 1, 2025

Verified Purchase

Rebekah

West Palm Beach, US

★★★★★ 5

Love!

Size: Large, Color: (100) White / White / Mod Gray

Ive tried so many no show socks but I love these. This is the 3rd set I've bought. They never slip off and the material is thin and breathable. Perfect for working out.

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Reviewed in the United States on March 2, 2026

Verified Purchase

Becky

Chelsea, US

★★★★★ 5

True no-show socks that don’t slide down!

Size: Medium, Color: (100) White / White / Mod Gray, Size: Medium, Color: (100) White / White / Mod Gray

This is the first pair of no-show socks I’ve tried that actually don’t slide down into my shoes. Trust me… I have tried lots of different pairs and this is the one! They fit perfectly. They’re not too thick and they’re obviously durable because I wash them after each wear, so daily.

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Reviewed in the United States on March 21, 2026