Expansion joints connect two fixed assemblies or pipes and allow movement due to service load, shock, or thermal cycles. They are made of elastomer, fabric or metal materials and feature a bellows-style construction. Convolutions permit misalignment, movement or isolation of the components that are joined together. Expansion joints can have a round, square, or rectangular cross-section. Rounded products often have a neck or collar that permits attachment with a hose clamp. Expansion joints with a flanged end usually attach to components with screws or bolts. Some expansion joints are used in plumbing or piping applications. Others are designed for vacuum or process-gas systems in which vacuum flanges and fittings connect runs of pipes or tubes to other sections of pipes or tubes, as well as to hoses, valves, pumps, chambers and vacuum components. Expansion joints for electrical conduits are also available.