At least two models of filing and sawing machine were made by the Italian Opus Company, the 120 and 140. Weighing approximately 270 kg and with a table 275 x 275 mm that could be swivelled 10° in four directions, the Model 120 had a saw blade and file stroke travel that was adjustable between 0 and 120 mm (0 and 4.72 inches). Driven by a 1400 r.p.m. 0.35 h.p. motor, the four rates of stroke were 70, 110, 150 and 280 mm (2.8, 4.33, 5.9 and 11 inches) per minute and the maximum thickness of work able to be filed or sawn was 70 mm. As supplied by the maker each new machine came equipped with a complete electrical installation,  table clamp-down kit, a set of six files -  the standard ones being 100, 125 and 150 mm (3.9, 4.9 and 5.9 inches) long), six file holders, six saw blades, six saw-blade guides, an air-blowing attachment, oil and grease guns, a light unit, a set of spanners and a handbook - a magnifying glass attachment was charged extra.
The Opus Model 140 was a very much heavier machine - it weighed around 410 kg - and was fitted with 400 x 420 mm table able to be tilted 15° in four directions. Power came from a 940 r.p.m. 0.75 h.p. motor connected to variable-speed drive system that used a mechanical expanding and contracting pulley system. The stroke travel could be set between a minimum of 10 to a maximum of 140 mm (0.4 to 5.5 inches) while stroke rates varied infinitely between 60 and 330 mm (2.36 and 13 inches) per minute. As the table could be raised and lowered through a range of 70 mm, the maximum thickness of work that the Model 140 could handle was a useful  100 mm (4 inches).
Those craftsmen with experience of "filing and sawing machines" will know that they are not what the layman thinks them to be - a rough-and-ready method of removing metal - but the exact opposite. While they were not intended for use in general workshops, they did find a valuable niche in better-equipped toolrooms where an expensive, and a top-class example (sometimes referred to as a die filer) could, in the hands of an experienced operator, produce almost miraculously-accurate results. Usually equipped with a tilting, square or rectangular table, almost any angle could be filed and many models would also double as a "fretsaw" for cutting out patterns and templates for use on copy lathes and milling machines. While some types were very simple and capable of only limited work, others such as the 1920s Beichle and its English-market model the Excel, were fearfully complex and would not only tackle relatively light work making tools, jigs, patterns, templates, embossing tools and moulds, etc. but also 1:1 copy milling, die sinking and basic turning, boring, milling and shaping - a number of accessories being available to assist with the latter operations. One well-known maker of die filers was the German precision machine tool company Thiel; their two Produro models, the 111 for small work and the 115 for larger, being beautifully constructed, long-lived and popular examples.
So useful was the filing machine considered that some makers of high-class American bench precision lathes of the early 20th century, such as the Pratt & Whitney and Waltham, offered them as bolt-on attachments - the Waltham having the luxury of a round table that, while remaining angled and at just one setting of the job, could be rotated for one complete turn in the horizontal plane, making it possible to file a square corner, with a clearance angle at each side. The Waltham lathe filing attachment was also available as a complete machine for bench mounting, driven by a round leather "rope" running over a 3-step pulley..