Price history on Walmart.com for
HART 20-Volt Lithium-Ion 6.0Ah Battery and 2-Pack 4.0Ah Battery (Charger Not Included)
See on WalmartProduct info
6X longer runtime with 6.0Ah Battery. 4X longer runtime with 4.0Ah Battery. Includes: (1) 6.0Ah Lithium-Ion Battery and (2) 4.0Ah 20V Lithium-Ion Battery Fade free lithium-ion power On-board fuel gauge Works with all HART 20V tools
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