PREMIUM PA12 DOT AIR HOSE: CheeMuii DOT air lines are made of high-quality Polyamide 12 nylon, meet D.O.T. FMVSS 571.106 approved, SAE J844 air brake system requirements, with corrosion resistance, high-temperature flexibility, high-pressure resistance and long service life HIGH-STRENGTH AIR TUBING: CheeMuii reinforced air hose has high impact and wear resistance, can withstand higher working pressure, and has a longer service life. At the same time, it has a certain degree of flexibility and can be easily bent to a certain extent without affecting normal use 1/4" TUBE WORKING INTENSITY: The 1/4" DOT air lines can be operated in pressures from vacuum to 500 PSI and in temperatures from -40 F to +248 F (-40 C to +120 C). Note: see the tubing manufacturer's recommendations for pressure and temperature mutations WIDE APPLICATION: The pneumatic tubing air line can be used for air suspension and air brake systems, perfect for semi truck/trailer/RV/automotive/vehicle repair air line leak, also ideal for industrial workshops, daily garden or lawn mower repair, towing machine hose connection, etc QUALITY ASSURANCE: We are confident in the quality of the DOT air lines, if you are not satisfied or have questions, don't hesitate to contact us, we are committed to providing you with quality service.