JB1 to JB4 Upgrade Kit

Marsoni

M251S

$175.00

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

JB1 to JB4 Upgrade KitUpgrades your existing BMS Stage1 to a EA888 JB4 BETA system. The JB4 BETA features CANbus connectivity for more advanced tuning, direct AFR control, advanced safety systems for boost, air fuel ratio, fuel trims, and engine knock, boost mapping by gear for improved traction, integrated water meth control, and much more. The upgrade kit cost is $125 outright. There is no longer a core exchange program available. After the upgrade you can keep your old

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Exchange/Return Notes

We offer a 30-day return/exchange service after receiving.
Final sale items are not eligible for returns or exchanges.
To process your return/exchange, please contact us at [email protected]
Please click here for more details>>> Return & Exchange Policy

I like to change my washing pads on the Eufy C20 every Friday (floors are vacuumed Mon, Wed, Fri and get washed on Mon and Fri as well). I will send the mop out too just to do the kitchen once I have had a big cooking session. These fit well and work as well as the original. I'm so happy to have extras as my laundry sometimes take several days to get caught up. Recommended.

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Reviewed in the United States on June 13, 2025

Verified Purchase

Amazon Customer

Cuba, US

★★★★★ 2

Poor quality

Color: 12pcs

I ordered these for my Eufy robot mop/ vacuum. While they fit great they are of terrible quality. They shredded on the first use and I have tile floors. Maybe I got a defective batch but I will not be buying these again🫤

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Reviewed in the United States on May 28, 2026

Verified Purchase

Caitlin

Phoenix, US

★★★★★ 1

Save your time and order the eufy brand.

Color: 6pcs

Started fraying immediately. Tried a different pair and had the same problem.

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Reviewed in the United States on May 21, 2026