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⛽ Don’t let bad fuel sink your ride—test it like a pro!
B3C Fuel Mechanic in a Bottle Gas Test Swabs are professional-grade, USA-made swabs designed to quickly detect fuel contamination. Ideal for boaters and vehicle owners, these swabs help prevent engine damage by identifying bad gas early, offering peace of mind and saving costly repairs.
| Best Sellers Rank | #70,274 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #73 in Lab Swabs |
| Customer Reviews | 4.2 out of 5 stars 61 Reviews |
R**N
Expensive but priceless
This worked great, saved us from bad gas in our boat.
R**I
Swabs look like good quality and functions as advertised.
It was shipped quick and came with two swabs. Easy to store and easy to use. If it saves my engine it is a great value. Swabs look like good quality and functions as advertised.
P**E
Price
For the price ok
A**R
This really works for water in the gasoline.
As far as water in the gas this showed it immediately. It saved me from damaging my engine and disposing of gas that didn’t need to be thrown away.
A**N
Great Fuel Tester !!
Living Off Grid I often fine that I have cans of gas that have been sitting for quite a while unused. This tester helps me verify if I can still depend on the fuel being OK to use.
G**.
Already expired
Swabs were expired. The tips were already blue. Don't buy
B**Y
Maybe it works maybe it doesn’t
Cheap
T**M
Woks as intended
Was aware Mechanic in a Bottle came with only three test swabs however wish it had included a dozen or more. Results were easy to interpret, quick and easy. I ordered a jar of Gasoila to keep on hand for future use. Although it only detects for water I don’t usually keep fuel beyond its useful life which is rather long because I use additives to extend the life.
Trustpilot
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