Amazon has 4-Count Brita Plus Water Filter Refills on sale for $16.89 when you clip the 35% Off coupon on the page and checkout with Subscribe and Save. Shipping is free w/ Prime or on $35+ orders.

• The BritaPlus high density water filter traps twice as many contaminants as the Brita Standard Filter
• 40-Gallon filter life for up to 2 months at a usage of 11 glasses per day.