Sunvalleytek via Amazon offers the USpicy Perfect Pedicure Callus Remover
for $19.99. Coupon code "DBGPA3XK" drops the price to $14.99
. Plus, Prime members receive free shipping
. (Non-members can spend $35 or more to qualify for free shipping; otherwise, shipping costs $5.33.) That's $35 off list and the lowest total price we could find. It includes two roller heads and requires four AA batteries (included).