Air Lift Fittings 21857 Air Lift Company has developed dependable air spring suspension products since our inception in 1949. All our efforts are spent ensuring your safety and comfort by designing, engineering and manufacturing the highest quality suspension products. Union Union; Elbow; 3/8 in. Tube x 3/8 in. Tube; Air Lift Union- Elbow 3/8in Tube X 3/8in Tube