1. Revolves supporting the belt on the side which carries loads and is used for carrying bulkmaterials, such as sand, earth, crushed stones, gravel, minerals, grain, etc. 2. There are various trough angles: 35°,45° 3.There are two type of idler: standard idler and forwardtilt idler. The forward leaning idler can be arranged along all length to prevent belt sway off center condtion.