Another Centec produced in smaller numbers - and one of the last to be made - was the No. 4; this was a much larger and heavier machine than the 2A and 2B and supplied as a horizontal miller only with a program-controlled and hydraulically-powered 10.5" x 40.5" table with 18 inches of longitudinal movement, 7 inches in traverse and 13 inches vertically. The table-drive system, powered by a 1.5 hp motor,  used Centec patents (which were applied for, but possibly never granted) which gave a very high thrust with a 300 inch per minute fast traverse facility; the feed was step-less and could be set to run from 0.5 to 50 inches per minute. The main spindle, with a 40 Int. nose, ran in three precision bearings with the one immediately behind the nose being a taper-roller bearing with an inside diameter of three inches; 10 speeds were provided, of 50 to 2000 rpm, by either a 3 hp or 5 hp motor. The machine was intended for high rates of production and one end of the table was left open so that swarf and coolant could drain away quickly and easily into a detachable collector; rigid stops with micrometer adjustment collars were fitted at each end of the table to allow precise setting for dead stop and reversing - as might be used in plunge cutting - and the spindle was arranged to stop automatically during rapid table returns in either direction. Four slots in the front end of the table were used to house adjustable trip dogs by which means the required horizontal program could be quickly and easily set. A one-shot centralised lubrication system was fitted which supplied oil to all the slideways..