Stabila ols 26 optical level with a 26 fold magnification in optical system no batteries required to use with the focusing and adjusting screw easily accessible it has a robust ip54 protection rated casing with easy grip shock absorbing soft shell and solid protection of optical unit also in front area magnification 26 fold minimum focussing distance approx 1m objective lens aperture 38mm protection class ip 54standard deviation 2mmkm view in objective upright diameter of field of vision at 10