Either it a stock shock or a good aftermarket shock they could all use a little protection! The main shaft on the shock travels up and down as the suspension travels and the only thing keeping dirt and debre out as well as oil in is a rubber seal at the shock body. Over time dirt on the shock shaft can act like sand paper which eats at the seal on each stroke and can eventually cause the seal to fail. A good set of shock covers will help keep dirt/mud and etc from reaching the shock shaft helping to keep it clean and extend the life of the shocks not to mention a set of shock covers like these from Pro Armor can add good looks to any bike.
These shock covers from Pro Armor are made of all weather, UV treated, water and dust resistant nylon with heavy duty elastic and velcro to make them easy to install and remove as well as keep them in place when on the shock. These come in sets of two so two kits are required for four shocks.