【Statement:】Kindly note that this item is suitable for viewing or reading only. It will shake quite a bit and make you uncomfortable if you need to touch or tap the device frequently. However it is inevitable due to some law of physics..【Using Tips:】1.When you are holding a heavy tablet, you could try to loop the gooseneck into a "S" shape or circle shape which would provide some more stability. 2.Bend using two hands and bend just the gooseneck when adjusting the position because it is stiff. Pull the device violently when adjusting may broke the nut. 3.Also, don't overtighten the base clamp too much so it won't break easily..【Reinforced Bolt Clamp Base:】Reinforced and thickened base. Won’t break easily. Fit for 3 inches(75mm) thickness countertop or headboard..【Flexible Stiffened Arm:】Made of Aluminium-Magnesium Alloy, stiffened material, very sturdy and flexible. 30in Overall Length from bottom to top..【Compatibility:】Compatible with any devices from diagonal 4.7 to 10.5 inches.