Attributes . Explosionproof, dust-ignitionproof; Smooth, rounded integral bushing in each hub protects conductor insulation; Accurately tapped, tapered threads for tight, rigid joints and ground continuity; Concentric ring interlocked design sizes makes possible smaller diameter, allowing use in tighter spaces; UNY unions are used for joining conduit and connecting conduit to enclosures, Facilitates modifications, permits removal of enclosures without turning or removal of conduit; Nipple not removable . Names