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Hydraulic Oil Service Plugs, 4 Large, 8 Medium, 16 Small

Based on 415 reviews
Condition: New
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$29.99
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Availability: In Stock.
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Arrives Thursday, Oct 29
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At a glance

Condition
New
Size
4 Large, 8 Medium, 16 Small
Model
MSR4L8M16S
Weight
1.02 kg
Color
Green/Yellow
Material
NBR rubber

Features 5

  • Push and twist to insert. For unpressurized systems only. Fits a wide range of sizes no need to find the right plug or cap. Operating temp: -10F to 200F (-23C to 93C)
  • Prevents oil leaks and keeps equipment clean. Hi-Viz green/yellow color reminds you of unconnected hoses, ports, and fittings during reassembly. Fits hoses, tubing, pipes, ports, and fittings incl. JIC 37 flare, 45 flare, push-on, and SAE O-ring. Cut to desired length. For industrial, commercial, and DIY use
  • Kit includes 4 large, 8 medium, and 16 small plugs. Small: 3/64"1/2" (113mm). Medium: 5/16"1" (826mm). Large: 1/2"1-1/2" (1238mm). Includes zip bag for clean storage
  • Made of oil-resistant, silicone-free NBR rubber. Resistant to conventional and synthetic oils, transmission fluids, gasoline, diesel, coolants, and water. Short-term resistance to ethanol-blended fuel and brake fluids. Test for compatibility before use

Description

Mess Stopper Hydraulic Oil Service Plugs are most commonly used to prevent oil leaks when servicing equipment and machinery. The plugs also keep your equipment and oil clean during servicing. Their gradual taper allows them to fit a variety of hole sizes, eliminating the need to keep and store the right size plugs and caps. Mess Stopper is made of oil-resistant, silicone-free NBR rubber. It is resistant to most oils and chemicals such as conventional and synthetic lubricating and hydraulic oils, transmission fluids, pure gasoline, diesel fuel, ethylene glycol coolants, and water. It has short-term resistance to ethanol-blended fuel and brake fluids. To ensure compatibility, always test the Mess Stopper for fluid resistance by immersing it in the fluid and observing for degradation.

Specs 12

Material NBR rubber
Brand Mess Stopper
Color Green/Yellow
Item Weight 1.02 kg
Brand Name Mess Stopper
UPC 703929688532
Number of Items 30
Number of Packs 28

Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, Oct 29

Yes, absolutely! You may return this product for a full refund within 90 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Top Amazon Reviews


works great!
Size: 4 Medium, 10 Small
I love these. I used them many times and I never had any issues. I bought them to plug coolant lines when I change out DEF headers on semi trucks, the trucks that use the hard plastic lines and you can't pinch them off.
Reviewed in the United States on October 4, 2026 by Brandon

Works great. Just don’t expect anybody to give them back!
Size: 2 Large, 4 Medium, 8 Small
I use these all the time. They’re flexible enough to go in 90° fittings. They seal instantly. Great for changing hydraulic hoses and not getting hydraulic oil bled all over you while changing a valve or hose.
Reviewed in the United States on July 23, 2026 by Hoffa Jr.

Easy to use and very flexible.
Size: 2 Large, 4 Medium, 8 Small
Great plugs!!! Used on 2006 Honda Accord 4 cyl to plug automatic transmission lines going into radiator during radiator replacement. So easy and worked great. Perfect seal.
Reviewed in the United States on July 7, 2026 by Peter Draghi

Works good when dry
Size: 4 Large, 8 Medium, 16 Small
These work well for keeping dust out of open lines. They are not designed to hold any pressure, and work better dry than oil covered. I've used them only in the upright position, upside down hasn't really worked for me. Overall good for the value.
Reviewed in the United States on October 12, 2025 by Moriah Crumrine

They work as they should and I will always buy them
Size: 2 Large, 4 Medium, 8 Small
I couldn’t have purchased a better product
Reviewed in the United States on June 1, 2026 by Ray

Nice and cheap insurance!
Size: 4 Medium, 10 Small
Handy, cheap way to keep crap out of your hydraulic system when opening lines.
Reviewed in the United States on June 28, 2026 by WebGuyDave

Work great
Size: 2 Large, 4 Medium, 8 Small
I've used these on hydraulic lines on a log splitter, power steering lines on my car, and transmission lines. Work as advertised, good selection of sizes and easy to cut down if you need to. Seal great,durable, easy to use, and a good value
Reviewed in the United States on May 26, 2026 by eaglecaps jh

If you deal with hoses containing fluid, hydraulic cylinder rebuilds etc. these are a must.
Size: 2 Large, 4 Medium, 8 Small
Not sure how I did without these for so long. Actually I used bolts, pins, pens, and anything else for normal hoses. When it came to hydraulic lines with metal connections I would use vacuum plugs and other odd and ends. First of all, the color! These are easy to see and even if they get soaked in hydraulic oil they stay bright. I have used these 1/2 dozen times from tractors to small engine repair, they work great. Second and most important, they work. You may have to swap to different sizes but all in all they seal good. I have no problem leaving these in for days while waiting on parts. I have yet to have one cone out when it wasn't suppose to. And last, professional. They just look good, with makeshift stoppers there is always a chance for contaminates or damage. With these they wipe clean and I haven't had any damage to them. ... show more
Reviewed in the United States on February 11, 2025 by Dewayne
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