25" 1/2" flex conduit. Reduced wall flexible aluminum conduit. Maintains all the strength and durability of steel, but is 2/3 lighter in weight. Designed to meet industry specifications for use with standard conduit connectors and device boxes. Meets UL Standard 1, NEC Article 350, and Federal Specification WW-C 566C. Due to the fluctuation of the copper market, Do it Best Corp. reserves the right to bill at the prices prevailing on date of shipment. We reserve the right to substitute similar quality by various manufacturers. 1/2" x 25", internal diameter: 0.625 minimum, 0.645 maximum; external diameter: 0.860 minimum, 0.920 maximum; 3" bending radius No. 55082122: 1/2" x 50", internal diameter: 0.625 minimum, 0.645 maximum; external diameter: 0.860 minimum, 0.920 maximum; 3" bending radius No. 55082103: 1/2" x 100", internal diameter: 0.625 minimum, 0.645 maximum; external diameter: 0.860 minimum, 0.920 maximum; 3" bending radius No. 55082321: 3/4" x 25", internal diameter: 0.812 minimum, 0.835 maximum; external diameter: 1.045 minimum, 1.105 maximum; 4" bending radius No. 55082305: 3/4" x 50", internal diameter: 0.812 minimum, 0.835 maximum; external diameter: 1.045 minimum, 1.105 maximum; 4" bending radius No. 55082303: 3/4" x 100", internal diameter: 0.812 minimum, 0.835 maximum; external diameter: 1.045 minimum, 1.105 maximum; 4" bending radius