Amazon offers Prime members the Tidy Cats Brand Breeze Cat Litter
with free shipping
. (Non-members can spend $35 to bag free shipping; otherwise, it adds $9.93.) That's the lowest total price we could find by $5, although most merchants charge $38 or more. This system uses cat-friendly litter pellets that purport to allow urine to pass through, while leaving solid waste on top for quick, easy removal.