Specifications we have three model:WY1A, 2W,WYA3 Determine range of refractive index (n D) 1.300 - 1.700 Determine range of the sugar content 0 - 95% Minimum scale unit of sugar content 0.25% Minimum scale unit of refractive index (nD ) 0.0005 Minimum inaccuracy of measurement 0.0003 Magnification of telescope 2X Magnification of reading microscope 22X weight WY1A:6.1Kg 2W:4.9Kg WYA3: 2.7Kg