Benefits The Suction Cup G4 is super simple, lightweight and has a small diameter soft base. The lever-style vacuum mechanism is simple and quick. Press the center button to the cleaned windshield and rotate the lever down. The clamp on the suction cup places any attached Ball2Ball™ arm or holder with a 20mm ball the closest to the mounting surface of any suction cup on the market. The 67 Designs' Suction Cup G4 is the least intrusive mounting option for aviators and their passengers. Product Details Carbon Fiber Series® Suction Cup G4, Arm and Device Holder allows you to install the suction cup mount on a flat and clean area of your aircraft windshield or side windows.  Ideal for easy on/off installation of your phone or other small device. Designed and Made in the USA. We do not recommend using any suction cup (from any vendor) with a longer than a 124mm (4.9") arm length. Using a longer than 124mm length arm in an 'a la carte' custom setup voids the warranty. Not designed for concave or convex curved windows or surfaces with any texture. Surface must be smooth and clear of all debris. Not designed to be used outside the cabin and never on an exterior surface in flight. Simple Installation Wipe down the smooth acrylic surface to ensure there is is zero debris like hair, sand or residue. Wipe off the soft rubber/TPU suction cup and ensure there is is zero debris like hair, sand or residue. Pull back the lever so it is above the 67 Designs logo button. It should be loose. Put the suction cup on the glass or acrylic surface in a flat area and ensure there is no edge on debris or a surround. Press the 67 Designs logo button down so the soft rubber/TPU cup is flat to the surface and pushing out the air. Gently, but firmly rotate the lever down while maintaining just enough pressure on the logo button to hold the suction cup in place. The button should be backing away from the suction cup body. Check the suction cup is secure to the acrylic surface by grabbin