Robinair (65060 Enviro-Guard Hoses with Ball Valves - 60", Set of 3 Enviro-Guard A/C service hoses feature a special barrier material that prevents virtually any permeation of refrigerant yet still remains flexible 60 inch long, 1/4 inch yellow, blue, and red hoses; 740 PSI working pressure; 3700 PSI burst pressure; includes in-line 1/4 turn ball valves to control refrigerant flow Brass 'Quick Seal' fittings - 45 degree on one end, straight on the other - provide a leak-free seal Coupler nuts feature deep knurling for a positive grip that enables quick finger-tightening Hose ends feature a strong six-sided crimp that provides a secure, reliable connection between the hose and barb - even at maximum pressure