The Product is Most vehicles manufactured after 1993 use r134a refrigerant. if you have a vehicle before this date and you haven't retrofitted it to use with r134a then you will need a gauge made for r12. aluminum block design with sight glass 72" standard hoses quick couplers anti-flutter design gauges additional access port professional quality attractive clamshell packaging. Produced with the highest grade materials. Satisfaction Ensured. Product is of great value and easy to use.