Belt and chain guides are used in conveyor belt applications to guide belts and chains and keep them aligned while reducing friction and wear. Tensioners help prevent belts and chains from slipping and breaking due to a lack of tension in the drive system. Elastomeric tensioners absorb vibration, withstand harsh environments, and do not require lubrication. Self-adjusting tensioners are spring-loaded to maintain constant pressure on a V-belt in a drive system, eliminating the need to make manual adjustments. Linear tensioners maintain tension in drive systems with chains that move over longer distances. Drive tighteners and shafts are components that make up a tensioning device.