16.25D x 18.75W x 53.25 H. (inches). Three ports. 4 inches diameter, 10.5 inches long. Tuned to 29 Hz. I'm actually using Aperiodic venting as used in the old Lockwood cabnets. With a shelf with felt lining below the driver, restricting flow to the ports which are in a chamber below. Usually Aperiodic vents are not tuned and have a shallow depth. However I'm tuning my ports to 29 Hz. I will test in my room and depending on how it sounds will stuff some or all the ports with sponge further enhancing the Aperiodic effect. That's only if the sound is too boomy. I may even seal the ports completely depending on how they sound.