Two yarns with this name: a single and a 2ply. The 2ply is typically higher in price and usually has the name Studio Donegal on the skein.

Studio Donegal is the Irish textile and garment business that gets its yarns from the spinning mill Donegal yarns. Donegal Yarns is the producer and sells its singles to retailers. Studio Donegal sells fabrics and garments and also a beautiful 2ply to handknitters.
Both yarns come from the mill and both are called Soft Donegal.

“This range is our Merino quality available in (3.8Nm) suitable for both weaving and 5 gauge machine knitting supplied on 1 kilo cones in oil.

It is also available as a 2ply (clean on 2 kilo cones) suitable for both handknitting and 2 ½ gauge machine knitting.

Using only the best wools it meets all the requirements of modern yarn with a soft handle, yet with its large flecks and having been spun in the traditional woollen spun method it has all the ingredients the traditional homespun Donegal.“