Special sieves with a built-in power vibrator for product handling by gravity or by air suction conveyor. Ideal for sieving dusty products used in chemical or food processes. Provided of a Teflon-coated grid with a mesh size of 1.5 mm. Automatic impurity expulsion system by way of a side hole. Composed of an eccentric mass power vibrator with adjustable output. Mounted on springs and anti-vibration cushions.