At Amazon get $3 off the purchase of select Duracell battery packs when you clip this coupon. Even better, most items can be purchased via Subscribe & Save, which takes an additional 5% off and yields free shipping. (Otherwise, Prime members get free shipping, or non-members can spend more than $25 to get free shipping.) With prices starting at $5.38 after the discounts, that's tied with our mention from three weeks ago as the best such offer we've seen from Amazon since last winter, when it offered a $5 Amazon credit with select batteries.

A best bet is the Duracell Rechargeable Batteries with Duralock Power Preserve 4-Pack (pictured), model no. DC1500B4N, for $6.49 with free shipping via the instructions below. That's the lowest total price we could find by $4. To get this deal:

1. View the Duracell Rechargeable Batteries with Duralock Power Preserve 4-Pack for $9.99
2. clip the $3 off coupon on the product page to cut it to $6.99
3. add it to your cart via Subscribe & Save for a final price of $6.49

Be sure to cancel Subscribe & Save once your order ships or you'll be billed for subsequent shipments. Amazon Prime membership is $79 per year; however, Prime is free for college students for six months, and free for parents and caregivers for three months.