The 421 belt scale weigh frame is specifically designed for high volume, low density applications where belt load and belt speed are moderate. This model is also available for hazardous, explosive areas, suitable for ATEX categories II2D and II3D (zone 21 and 22). Two BM11 bending beam, hermetically sealed load cells are mounted on adjusting plates on the outside of the conveyor stringers to create a stable base. A precision weigh roller is tensionlessly mounted directly on the load cells.