text: the e machine number under the sliding door says.       model e machines w3107   s/no: cca61  500  35533?   the first number is your model number  http://www.shop.com/op/aprod-p38910525-k24-g4-~w3107+-nover?sourceid=13  the second is a serial number. basically everything of value in this world is given a serial number. it helps track assets and return them if stolen.