CVA was an English manufacturer of automatic gear cutters, gear hobbers, automatic and small capstan lathes, dieing presses, milling and die-sinking machines and - it is thought - one small jig borer.
Jig borers come in a variety of sizes and types, from the ones used in watch, clock and instrument making -  Assa and Hauser, for example - through to high-precision larger types such as the Downham, S.A.D.A.M.L., Leitz, Wolf Jahn/Leinen/Ultra/Excel/Sigma /B.C.A. Models of a similar single-column design to the CVA include the American Vernon and Linley, the somewhat heavier Matheys from Belgium, the Italian Emtoc, and from Switzerland the Perrin and the costly smaller Hauser models. All the latter types, although incapable of large and heavy jobs, would have found homes in busy toolrooms where tying up an expensive Klob, SIP, Newall, ABA, Fimap, Linder, Moore, Dixi, Omega, DeVlieg, Pratt & Whitney, Mitsui, Manix or Fosdick would have been uneconomic.
A most unusual jib borer - of an unique design - was the American Autometric..