Type 15 Signal Box Kit - Wood Base - OO GaugeType 15 Signal Box Wood Base Construction This style of Type 15 signal box first appeared in 1954. There were 2 main construction types (all wooden and brick base) and a variety of configurations. Kit form including mdf, birch ply, laserboard and clear acrylic parts. Available in left and right hand versions Interior has etched floorboards and plain walls for you to add your own detailing. Build instruction available on our YouTube channel