Extend the 3018Pro CNC Y- from 290mm to 450mm to get 320 x 450mm base area, 320 x 370mm motion area, 300 x 320 actual stroke. Upgrade your 3018Pro CNC X- with 390mm T8 lead screws and aluminum knobs for even easier handling. Compatible with most 3018 CNCs, 3018 Pro, 3018 Pro Max, etc. Note that your 3018Pro CNC should be equipped with 8mm T8 post screws, 10mm rails, and no holes for the rail end plates. Upgrade 3018Pro CNC's product and get one size bigger. Easy to assemble. Type:A color:Black + Silver Material:Aluminum alloy Package Contents: 1 x Expansion Board 2 x Countertop Connection Plate A 1 x Countertop Connection Plate B 2 x Countertop Connection Plate C 2 x 2040 aluminium profiles (450mm) 1 x 8 mm T8 screw (390mm) 1 x 8 mm T8 screw (470mm) 2 x 10 mm guide rods (450mm) 2 x knobs 2 x Nuts 24 x Slider Nuts 2 x M5X14 screw 8 x M5X16 screw 8 x M5X20 screw 8 x M5X24 screw Only the above package content, other products are not included. Note: Light reflection 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.