The Spiro M1 90% from MISSION is a dart set with barrels of 90% Tungsten and is a very high quality dart set. Spiro darts are part of the newest range of darts from Mission darts. These darts are a feast for the eyes and are finished with black graphite pvd coating. The Mission Spiro darts come in two versions, both a straight barrel and a front loaded variant. The excellent grip and special grip patterns offer more than enough grip for every dart player. This dart set comes in 3 weights; 21-23-25 grams. 21G = Barrel Length: 52.00mm, Barrel Width 6.20mm. 23G = Barrel Length: 52.00mm, Barrel Width 6.50mm. 25G = Barrel Length: 52.00mm, Barrel Width 6.80mm.