Ergo360 Chair Armrest Arm Pad Covers - Genuine High Density Memory Foam for Ultimate Elbow Comfort (2 Piece Set) Genuine High Density Memory Foam Armrest Covers Are The Easiest Way To Upgrade Office Chair Arm Pads. Transform your hard factory installed armrests into the most comfortable chair arms you have ever used. The 3/4" thick High Density Memory Foam provides excellent cushioning that distributes pressure more evenly across the elbows and forearms. And if you are looking for even more cushioning, a set of 1/2 inch thick optional foam inserts are also included. These arm pad covers stretch around most factory supplied chair armrests from 7" to 11" in length and up to 4" wide. They are covered with soft black fabric with an elastic opening for a snug fit. Pricing is per complete set.