DeWalt's 4Ah 20V Max XR Powerpack Battery is 60% off for Amazon's big sale

While you can easily find a decent sale on DeWalt gear on Amazon, what you won't see too often is a good discount on its high-performance batteries, like its 20V Max XR Powerpack options—let alone a meaningful markdown on the powerful 4Ah models. Luckily, right now is one of those times, as this amped-up battery is 60% off during Prime Big Deal Days (but it's selling out fast).