Rack or Chassis
A chassis is the physical frame or structure of an automobile, an airplane, a desktop computer, or other multi-component device.
A Rack is the framework, typically with rails, bars, hooks, or pegs, for holding or storing things.
6ES5701-2LA12 - Siemens
Simatic S5 ER 701-2 Mounting Rack for S5-115U/F Expansion Units with 7 Free Module Slots for Distrib..