“Just before end gates a U-shaped selection gate, existing of a galvanised steel round tube 50 mm. Bottom tube 100 cm above floor, top one 20 cm there above. Gate hinges on rear portal to the inside, where the hinge is tilted a bit, so the gate closes automatically, when a cow has passed it. Magnets on side wall lock the gate in open position. The gate can be taken out on a multiple deck vehicle.