VEVOR 2X 15-1500mm Linear Guideway Rail with 4Pcs Pillow Block Carriage Bearing Block for 15mm Slotted Block Square Block Linear Rail Routers CNC Set

Can the rails be mounted in a vertical orientation, with the rail parallel to the floor? As an example, imagine I want to mount two of these along one wall of my workshop horizontally, such that the rail is screwed to the wall, and the carriage runs left to right, rather than vertically. If these can be used in this orientation, what load can I put on them? Thanks for your assistance.