We strongly recommend using the cover, as it prevents older chicks from perching on top of the plate and keeps top of plate clean. An alternative to a heat lamp that uses much less electricity. Uses 66 watts/hr. 16″ x 24″ heat plate accommodates up to 50 chicks. The bottom of the plate will reach approximately 125 degrees when fully heated. Allow the plate 1 hour to heat the unit before placing the chicks under it. As the chicks grow, increase height of the plate above the bedding with the adjustable push-button legs. Plate is most effective when chicks can just touch the plate, especially when they are newly hatched. Heating plate is made of ABS plastic and polyurethane insulation. Requires 110 volt outlet. Has 70″ cord length. 1 year limited warranty on electrical heat plate unit.