Amazon.com: Naturesroom Sunbrella Patio Cushions - 20.5" W x 49" L x 2" T, Outdoor Adirondack Chair Cushion with Comfort, Style & Durability Designed for Outdoor Living - Made in The USA :
Casco Bay Adirondack Chair Seat Cushion, Stripe | Cushions & Pillows at L.L.Bean
Amazon.com: 47" x 21" x 2" Adirondack Chair Cushion with Ties (Sunbrella Aruba) : Patio, Lawn & Garden