This DK weight yarn from Robin's Promise yarn is a 4 ply made with 75% Superwash merino and 25% nylon.  Each 100g skein is approximately 245 yards.  This yarn is hand dyed in small batches in Williamsburg Virginia.  It is suggested you alternate skeins in a project because each dye lot may be a little different.  

Recommended US 5 to 7 or 3.75 to 4.5mm.  You can machine wash on cold and gentle and lay flat to dry.  You may want to hand wash this yarn instead.  

Photos from Robin's Promise.