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9.0Ah Replacement Battery for DEWALT 20V/60V FlexVolt (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.

Generic

$68.39

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

Spec9.0Ah Replacement Battery for DEWALT 20V/60V FlexVolt (2-Pack)Ryobi 40V Battery and Charger Kit, 4.0 Ah Lithium-Ion Battery Set OEM OP4040 + OP403A
PlatformFlexVolt40V
Voltage20V/60V MAX40V MAX
Capacity9 Ah4 Ah
Typehigh-outputkit
Genuine OEMNoYes
Fuel GaugeNoNo
Warranty0 years3 years
Price$68.39$109.96
Rating6.5/108.5/10
Buy on AmazonBuy on Amazon

Pros & Cons

9.0Ah Replacement Battery for DEWALT 20V/60V FlexVolt (2-Pack)

Pros

  • Two 9.0Ah packs for less than the price of one genuine DEWALT DCB609
  • Seller lists compatibility across a wide range of DEWALT 20V/60V FlexVolt model numbers
  • High per-pack capacity on paper for demanding FlexVolt tools

Cons

  • Third-party replacement pack, NOT covered by DEWALT's tool warranty — any tool or battery issue is handled by the third-party seller, not DEWALT
  • Buyer must independently verify voltage and platform fit against their specific DEWALT 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; unbranded listing with no verifiable warranty terms

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

9.0Ah Replacement Battery for DEWALT 20V/60V FlexVolt (2-Pack)

A genuine DEWALT FlexVolt pack like the DCB609 remains the safe default; this unbranded 9.0Ah 2-pack is a cheaper aftermarket option but comes with no DEWALT warranty, so verify fit and buyer protections before relying on it.

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.

9.0Ah Replacement Battery for DEWALT 20V/60V FlexVolt (2-Pack)

$68.39

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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