Mechanical scale features First Class, Express, Priority and Parcel Post rates. Trim, compact scale housed in a durable case. The overlay is removable, color coded and easy to update without taking scale apart. Scale Type: Postal For Carriers: USPS Electronic/Mechanical: Mechanical.SBWMPS5. MPS5. Salter Brecknell Salter Brecknell Mechanical Postal Scale.