2 Pack 4.0Ah 20V Tool Battery Replacement for Worx Battery 20V PowerShare WA3525 WA3575 WA3520 Compatible with Worx 20 Volt Cordless Tool WG890 WG891 (Not for Nitro Proven Power)

What It Is

This is a 2-pack of 4.0Ah 20V lithium-ion replacement batteries designed for Worx PowerShare 20V cordless tools, including lawn mowers, trimmers, blowers, and chainsaws. It offers higher capacity than standard 2.0Ah packs for longer runtime.

Fitment & Compatibility

• Exact models: Replaces Worx WA3525, WA3575, WA3520. Compatible with 20V PowerShare tools like mowers WG890, WG891, trimmers WG163, blowers WG520, etc.
• Not compatible: Does not work with Worx Nitro Pro (40V or 60V) or any 40V/60V tools. Check your tool’s voltage rating on the battery port.
• Physical check: Measure your existing battery (approx. 4.7 x 3.1 x 2.6 in) and ensure it slides into the tool’s cavity without forcing. The terminal layout matches WA3525-style packs.
• OEM vs aftermarket: This is a third-party replacement, not Worx OEM. If your tool is under warranty, using this may void coverage.

Key Things to Know

• Installation: No tools needed—slide battery onto tool until it clicks. Remove by pressing the release tab. Takes 10 seconds.
• Charging: Use any Worx 20V PowerShare charger (e.g., WA3740, WA3880). Do not mix with 40V chargers. Charge time ~2–3 hours from empty.
• Gotcha: Some users report slightly shorter lifespan than OEM packs (200–300 cycles vs 300–500). Keep away from extreme heat/cold during charging.
• Performance: 4.0Ah gives ~2x runtime of standard 2.0Ah packs, good for medium lawns (up to 1/4 acre on a mower).

Should You Buy It

Buy this if you need affordable backup batteries for multiple Worx 20V tools and don’t mind a non-OEM brand. Skip if you require OEM warranty, or if you own Nitro Pro tools—this won’t fit. For light-to-medium yard work, the price per amp-hour is solid.