Bottles of Purex Crystals are buy one get one free this month at Walgreens. Buy two and submit for two $1.00 Checkout 51 rebates. (The offer has a limit of two. To get the rebate twice, increase the quantity of $1.00 rebates requested after snapping a photo of your receipt when you redeem.) Plus, there is a 4th of July Bonus through Checkout 51; redeem two select offers and receive a $0.50 bonus on Friday. The final price is $1.75 per bottle!