chalkboard Thickness0.1 to 0.4mm , width 1000,1200mm .our blackboard is the surface material for writing board, it used in processing small board in school and office. It has good market in educational office field. Each coil weight: 3-5 TonInner diameter: 508mmOne 20 container: 6-7 coils ,around 25 tonDelivery time : 14 days after received deposit