monobloc

[mon-uh-blok]

adjective

denoting or pertaining to the casting of a complex metal object as a single piece rather than in separate parts.

Origin of monobloc

From French, dating back to 1905–10; see origin at mono-, block

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

The case is a rubber "Monobloc" construction, that is, the entire case is pressed into shape at one time.
The Automobile Storage Battery
O. A. Witte