1.Adjustable,Shock resistance,Wear-resistance. 2.This comfort armrests offer you added comfort whilst driving, which are pivoting and adjustable. 3.These are commonly used on Car, for , Motorhomes, for , Boats, Trucks etc. Product name: adjustable seat armrest Adjustable range: 90 Placement on seat:left Recommended mounting height: the distance between seat cushion and the underside of the armrest is 11cm ( or up/down 2cm according to you need) Installation: 1.Open the cover of the seat back. 2.please sit on your seat and make the mark on the position where is the most comfortable to you. 3.drill two holes on the mark you have made. 4.fix the armrest mount to your seat by screw given. 5.open a little hole on the sponge, then take the axis out of the sponge. 6.As for the cover, it is the same with last step. 7.Fix the armrest to the parts from the outside, and fix the screw. 8.Put on the lid. Material:Plastic and metal colour:Black Package Contents: 1 * seat armrest Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.