The Mastercool 91580-B Portable Electronic Charging Station features a lightweight, durable, steel frame cart that contains all the necessary tools to quickly and conveniently charge A/C systems including a 1-stage 3 CFM vacuum pump, 2-valve manifold, and charging scale. Use of this station and the rugged die-cast electronic scale eliminates the need for different sized charging cylinders. Users can simply place the refrigerant cylinder on the scale and charge.