7" STAX® Coil Perc made on 65mm tubing with a 34mm plastic joint clamp. Fits any STAX® base, perc, or mouthpiece.The STAX coil perc is 7" tall and made on 65mm tubing. Smoke travels up the central stem before descending through the coil. The prolonged exposure to water cools the smoke, and the thin space between the edges of the coil and the interior of the perc creates powerful bubbling diffusion. The coil perc can accommodate any STAX base, mouthpiece, or perc and works best with approximately 2" of water.