EngineerSupply Is Now A Northwest Instrument Authorized Dealer. After careful consideration to source another value-added source of surveying equipment, we decided to apply to Northwest Instrument. They make quality surveying equipment with value in mind. Their equipment will hold up under daily use and save you some money. Northwest Instrument makes Transits, Levels, Rotary Lasers, Surveying Tripods, Prisms, and Theodolites.