A series of enclosures made from ABS with a structured surface that is ideally suited for accommodating portable instruments, displays, receivers etc. Sizes 3, 4, 5 and 8 have 2 removable front plates. Sizes 6, 9, 10 and 11 have 1 removable front plate. Sizes 1, 2, 7 and 12 are enclosed half-shells; 7 and 12 also have a recessed surface, e.g. for inserting membrane keyboards. All enclosures are easy to machine and drill in order to accommodate installations or to mount components.