Safety Guard Chain Idlers are design to prevent serious injury and jamming of chain assembly on gate operators. They are easy to install and provide a quiet smooth action. The safety guard cover is made of UHMW plastic and has a Bronze iolite bushing with black finish. Has a 3/8" thick back mounting plate with 3/8" mounting holes. Available for rear and/or mid-mount application. Accommodates 90-degree and 180-degree Chain assemblies.