Tanga offers the Furhaven Orthopedic Pet Mattress in four sizes, as listed below. Shipping adds $2.99. Each mattress features a zippered cover and water-resistant bottom. The deals:

• Furhaven Orthopedic Small Pet Mattress for $11.99 ($9 low)
• Furhaven Orthopedic Medium Pet Mattress for $14.99 ($10 low)
• Furhaven Orthopedic Large Pet Mattress for $20.99 ($10 low)
• Furhaven Orthopedic Jumbo Pet Mattress for $28.99 ($11 low)

A close price: Overstock offers it in three sizes, for $1 to $3 more, depending on size.