Type 21 LPX chain 78 drive links. The high performance chain for professional users who use chain saws .325"pitch. Thickness 0.58 1.5 mm. Suitable for various saws, Alpina, Black & Decker, Bosch, Challenge Xtreme, Dolmar, Hitachi, Echo, Homelite, Husqvarna, John Deere, Jonsered, landxcape, McCulloch, Ryobi, Stihl. Dependent on manufacturer specifications, current guide bar and chain.