Click on link below for Amada Brochure with specifications:
https://www.amada.com/america/brochures/general-fabrication/ID40IV-HP-
NT/html5/index.html?&locale=ENG
Cast iron gridded rectangular box section .Grid pattern with allignment bushes and threaded inserts for ease of set-up. Ground flat parallel and perpendicular for accuracy. To suit verticle or horizontal machining centre applications.