Top and bottom heated modular holding cabinets for hot food holding The Carter-Hoffmann M series hot food modular holding cabinets feature the latest in modular holding technology. They have top and bottom heat, with separate controls, individual pan timers, alpha-numeric displays and self contained food covers.  Programming for menu settings can be done manually or via USB port. Each pan can have up to 25 pre-programmed menu settings.  Models can have single-sided or pass-through access to pans.  Pass-through holding cabinet models have rear displays for temperature and time.