Introduced in the mid-1960s, the Kearney & Trecker S Series joined the later TF Series, Series 1224, 1500 and 2000 and C12 millers as the company's last ranges of conventional 'manual' machines - that decade seeing the introduction of NC controls and then a gradual change to computer controls (K & T were experimenting with NC controls as early as 1958). Despite most competitors using V ways machined into the top of the column to secure overarms, the horizontal versions of the S Series still used the twin round bars that had been a feature of K & T machines since 1912 - though the 415 S-15 and 205 S-12 with their self-powered, gearbox-equipped ram-heads, did have V-ways - while also retaining a separately-driven horizontal spindle. The 'standard' horizontal range consisted of the 307 S-12, 415 S-15, 310 S-15, and 415 S-15, the vertical only versions being the 205 S-12 and 415 S-15.
A wide range of accessories was listed, including a sliding vertical head with a most unusual power-feed bracket that transmitted drive from the table to give nor only power feeds but a rapid feed to the in and out travel. Other vertical heads included two swivelling types, one with a handwheel for fine feeds and the other a universal version with a 2-axis swivel; a third high-speed (31 to 25000 r.p.m.) universal type had 10" of cross movement controlled by the machine overarm handwheel while the "Tri-D" head - for the horizontal machines only - was claimed to be capable of producing almost any geometric shape "employing straight lines, radi or angles using only simple arithmetic". Other items consisted of universal spiral dividing heads with a power feed drive from the table drive to give 1300 different leads for spiral milling, though a special 'low-lead' drive was also listed that gave 40,000 leads by power from 0.022" to 2918" with many short leads able to be stepped up and down in increments as small as 0.001". Also available were hand-turned and powered rotary tables, machine vices and both crane-type and hydraulically-powered parking devices to store vertical heads ready for ready for immediate use. All the models and their various attachments are shown and described in the following three pages..