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Epowon 5.0Ah Replacement Battery for Milwaukee M18 (2-Pack) vs Ryobi 40V Battery and Charger Kit, 4.0 Ah Lithium-Ion Battery Set OEM OP4040 + OP403A

Head-to-head spec comparison to help you pick the right battery for your needs.

Epowon

$57.99

Buy on Amazon
vs

Ryobi

$109.96

Buy on Amazon
Deciding between a genuine pack and a cheaper aftermarket one? Read our honest genuine vs aftermarket batteries guide.Read the guide →

Spec-by-Spec Comparison

SpecEpowon 5.0Ah Replacement Battery for Milwaukee M18 (2-Pack)Ryobi 40V Battery and Charger Kit, 4.0 Ah Lithium-Ion Battery Set OEM OP4040 + OP403A
PlatformM1840V
Voltage18V40V MAX
Capacity5 Ah4 Ah
Typehigh-outputkit
Genuine OEMNoYes
Fuel GaugeNoNo
Warranty0 years3 years
Price$57.99$109.96
Rating6.8/108.5/10
Buy on AmazonBuy on Amazon

Pros & Cons

Epowon 5.0Ah Replacement Battery for Milwaukee M18 (2-Pack)

Pros

  • Two 5.0Ah packs for close to the price of one genuine Milwaukee M18 battery
  • Seller claims compatibility with several Milwaukee M18 battery model numbers
  • Higher combined capacity per dollar than a single genuine M18 pack

Cons

  • Third-party replacement pack, NOT covered by Milwaukee's tool warranty — any tool damage or safety issue is between you and the third-party seller, not Milwaukee
  • Buyer must independently verify voltage and platform fit against their specific M18 tool before use
  • A working buying link is not proof of safety, cell quality, or real-world performance — we have not tested this pack
  • No manufacturer-backed warranty; seller return policies vary and are not guaranteed

Ryobi 40V Battery and Charger Kit, 4.0 Ah Lithium-Ion Battery Set OEM OP4040 + OP403A

Pros

  • Bundles a 4.0Ah 40V battery (OP4040) with a charger (OP403A) in one genuine Ryobi kit
  • 4.0Ah is a mid-to-high capacity pack for the 40V outdoor-power platform
  • Currently in stock on Amazon
  • Genuine Ryobi OEM parts, not aftermarket

Cons

  • Only one battery included — no second pack for hot-swapping on longer yard jobs
  • 40V packs are heavier than ONE+ 18V packs, worth weighing if you're carrying it around
  • We haven't independently timed a charge or measured runtime; 4.0Ah is Ryobi's stated rating

Our Verdicts

Epowon 5.0Ah Replacement Battery for Milwaukee M18 (2-Pack)

Genuine Milwaukee M18 packs are the safe default; this Epowon 2-pack is a lower-cost aftermarket alternative, but it carries no Milwaukee warranty and buyers must verify fit themselves before trusting it in an M18 tool.

Ryobi 40V Battery and Charger Kit, 4.0 Ah Lithium-Ion Battery Set OEM OP4040 + OP403A

A genuine Ryobi 40V battery-and-charger bundle with a solid 4.0Ah pack — practical if you're buying into the 40V outdoor platform or need a spare set.

Epowon 5.0Ah Replacement Battery for Milwaukee M18 (2-Pack)

$57.99

Buy on Amazon

Ryobi 40V Battery and Charger Kit, 4.0 Ah Lithium-Ion Battery Set OEM OP4040 + OP403A

$109.96

Buy on Amazon

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