The MV-40X ValuMax® Microscope Objective Lens has a 40x magnification, 0.65 numerical aperture, 4.4 mm focal length, and 5.7 mm clear aperture. It uses a standard RMS thread, 0.800-36. The objective is corrected for a rear conjugate at 187 mm. The lenses are antireflection coated with MgF₂ for the visible spectrum. This 40x objective is suitable for use with either the Model 900 or 910A spatial filters. MV- series microscope objective power is based on a 187 mm tube length. MP = 187 mm/f