The A 3/5 is a four-cylinder-composite-steamengine design "De-Glehn", it owns three coupled drive axles and a two axle first running bogie. This locomotivetype was ordered by the Jura-Simplon-Bahn at the SLM in Winterthur. In year 1902 two prototype were delivered. Until 1909 the SBB ordered 109 locomotives of this type.
The exterior high-pressure cylinders act on the middle drive axle, the lightly diagonal arranged internal low-pressure cylinders act on the frist drive axle. Especially to mention is, that there are used two types of controls. The exterior driving gear owns a "walschaert-control" and the internal driving gear uses a "joy-control". The company numbers 703-748 have been delivered with four-axle tender, all following locomotives maintain a three-axle tender.
- Loco number 705: black/dove grey with four-axle tender
- Loco number 710: black with four-axle tender with wooden buildup
- Loco number 775: black with three-axle tender