With press of button, properly aimed Models PD22/28 measure target distance to 500 ft with ±1/12 in. accuracy in just 0.3 sec. Built-in functions calculate height and width of building from single location; determine concrete required to pour foundation; and audibly dictate spacing for studs and stanchions. Spike and bubble level facilitate corner and horizontal measurements, respectively. Both models take 8,000 readings on single pair of AA batteries. Model PD28 stores 1,000 readings with job and measurement codes for PC upload.