Amazon has the Amazon Basics 3lb Epsom Salt (Unscented) on sale for $3.35 - 15% off coupon (check "Save an extra" box, eligible on first S&S order for this product) - 5% off with Subscribe & Save (can cancel anytime) = $2.68 with free shipping on $35+ or with Prime. A slight better price per pound than the 4lb bag at Walmart.