Check the listing for details. String Trees Barrel Style Chrome 7mm Set of 2. Color: Chrome, Condition: New. Listed at 9.49 USD. String Tree, Barrel Style 7mm spreadfor electric guitarsChrome 7mm string spreadSold as Pair with mounting screws. Specifications:Chrome FinishBarrel Style sold in pairsBase is 5mm (13/64") diameterTotal height including barrel is 8.6mm (11/32")Barrel width is 11.2mm (7/16")Mount diameter is 5mm (3/16")String Spread (center to center) is 7.0mm (slightly larger then 17/64")Screw is 2.1mm (#2) x 14.7mm (37/64")Screw length beyond base of roller is 6.1mm (1/4")Good replacement or new application barrel, designed for removing the slack from the strings and creating a correct pitch for the string behind the nut.Please note, there are two different heights for this type of product. This is the higher unit. Many American and some MIM style setups require a low profile tree for this type of application.PLEASE NOTE: These are very fine screws, they will break if not mounted correctly..The shank on this screw is 1.90mm (just over 1/16"). It is recommended you use a #50 or #49 drill bit and use screw wax to insert.