Convenient to operate without oil. Cylinders and pistons are made of premium materials, making the pump strong and durable. An extra large unit that features eight (8) 1/4 inch variable output outlets and uses 24.0 watts of electricity per hour. 20 liter per minute total output at 2.2 PSI per outlet. Measures 9.5 inches long by 7 inches wide by 5.125 inches tall, weighs 5 pounds.Uses standard airline tubing.