Convenient to operate without oil. Cylinders and pistons are made of premium materials, making the pump strong and durable. A compact unit that has a single (1) 1/4 inch fixed-rate outlet and uses 3.0 watts of electricity per hour. 1.8 liter per minute output at 1.75 PSI. Measures 4.75 inches long by 2.6 inches wide by 2.5 inches tall, weighs .55 pounds. Uses standard airline tubing.