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From the Catalog
Real products with verified specs. Tap one for the full data sheet.
Gear for this build
In stock at our partner shops — real prices, shipped from people who run this stuff.
JS Alternators
JS Alternators High-Output Alternator
250A–400A+ hand-built in the USA. Find the fit for your year/make/model.
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Sundown Audio
Sundown SA150-975L Super-Cap Battery
What a capacitor pretends to do — real stored energy for voltage sag.
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Sundown Audio
Sundown Full Tilt 50' 1/0 AWG Cable
50 ft of 1/0 AWG power/ground — the gauge most big-three upgrades call for.
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Stealth Energy
American Bass Stealth ST-750 75Ah AGM
75Ah AGM — deep reserve for high-draw audio and dual-battery setups.
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JS Ultimate Sounds and JS Alternators are run by the ShowUp team — buying there supports the site. Prices as listed at the shop.
Need more output?
JS-Alternators builds custom high-output alternators
For car audio, offroad, marine, and motorsport applications. Hand-built, dyno-tested, lifetime warranty.
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