Double flares soft steel tubing up to .040" (1mm) wall thickness. Single flares soft copper, aluminum and brass tubing. Includes hardened bar assembly with seven threaded dies (1/2", 1/4", 4.75mm(3/16''), 5mm, 6mm, 8mm (5/16'')& 10mm), yoke with swivel tip and sliding "T'' bar and matching double flare adapters . Complete with instructions , packed in blow mold case .