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

This weed eater trimmer line is pretty tough. Although there was only 12 spools in the box, but the Description says 15 spools, And this trimmer line is a lot tougher than the previous line I was using. I used very little of it on the first spool, which is great these Worx trimmer line spools fit perfectly and function perfectly this is a great product to purchase, and I will highly recommend them. if you just have a small amount of weed eating to do I would recommend getting these spools for your worx weed eater.

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Reviewed in the United States on March 30, 2026

Verified Purchase

Whiting, US

★★★★★ 5

Good product for the price

I bought for my Worx trimmer and they work great. Even though Worx offers free replacements, when you add shipping onto the "Free" order..it costs more...this price is well worth it.

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Reviewed in the United States on May 26, 2026

Verified Purchase

Liv2Read

Lexington, US

★★★★★ 5

Fits my weed eater perfectly

Fits perfect and does a great job. Easy to install. 15 pcs will last a ling time

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Reviewed in the United States on May 2, 2026