Compatible with chainsierras: Echo CS-310, CS-400, ECS-150, S2600 only 600, 638, 6238, 6240, 606va Sterwins 18594450, PCS38, PN3800 and more low vibration and setback for optimal performance-designed for owners of homes and gardeners. For motorcycle models with 3/8 step, .050 (1.3 mm), 53 links the narrow cut (narrow kerf) requires less energy allowing a more efficient job to finish your task quickly and easily: use Always swords designed for narrow cut chains