RYOBI 40-Volt 4 Ah High Capacity Battery and 40-Volt Lithium Rapid Charger Combo Kit (OP40404 & 0P406VNM)

What It Is

This combo kit includes a Ryobi 40-Volt 4 Ah high-capacity battery (OP40404) and a 40-Volt lithium rapid charger (0P406VNM). It’s designed to power Ryobi 40-Volt cordless lawn mowers, trimmers, blowers, and other OPE tools, providing longer runtime and faster recharging than standard 2 Ah packs.

Fitment & Compatibility

• Brand lock-in: Works only with Ryobi 40-Volt tools and chargers. Not compatible with 18-Volt, 40-Volt cross-brand, or other voltage systems.
• Battery model: OP40404 fits all Ryobi 40-Volt tools (including push mowers, self-propelled mowers, string trimmers, blowers, chainsaws). It’s a drop-in replacement for older 2 Ah, 4 Ah, or 5 Ah packs.
• Charger model: 0P406VNM charges all Ryobi 40-Volt batteries (2 Ah, 4 Ah, 5 Ah, 6 Ah). It will not charge 18-Volt or 36-Volt batteries.
• Physical check: Battery dimensions are roughly 6.5 x 4 x 3.5 inches. Ensure your mower’s battery compartment has enough clearance (some compact mowers may fit snugly with tall packs). Charger input is 120V AC standard.

Key Things to Know

• Runtime vs. weight: 4 Ah provides about 40–50 minutes of mowing on a 20-inch deck (depending on grass and speed). Heavier than a 2 Ah pack (approx. 1.5 lbs more) but lighter than a 6 Ah.
• Charging speed: The rapid charger fills a dead 4 Ah battery in about 60 minutes—roughly half the time of the standard charger.
• No installation needed: Battery clicks into any Ryobi 40V tool; charger plugs in and works immediately. No tools or wiring required.
• Common gotcha: This is a combo kit—buying separately costs ~$30 more. Verify you’re getting both items in one box (OP40404 + 0P406VNM). Some listings sell only the battery or charger.

Should You Buy It

Buy this if you own any Ryobi 40-Volt outdoor tool and need longer runtime than the standard 2 Ah battery, plus a faster charger to minimize downtime. It’s ideal for medium-sized lawns (up to 1/4 acre) and users who want one reliable battery/charger pair without hunting for separate deals. Skip it if you already own a rapid charger or only use small tools (trimmers) where a 2 Ah pack suffices.