Application Field: Machine vision microscopic inspection Industrial testing, especially electronic component testing scientific research Education industry This zoom c mount lens is representing the standard main magnification 0.7X-4.5X, objective magnification 0.75X and TV magnification 0.5X. This product adopts the design scheme of limited far-conjugate distance optical system. Five basic modules are: continuous magnifying body, auxiliary objective lens, TV lens, bracket adapter and optional module. Optical parameters: Bulk ratio: 0.7X-4.5X System multiplier: 0.26X-1.69X NA: 0.012-0.053 Working distance: 300mm Diagonal visual field: 22.86-3.56 Matching camera size: 1 or 3in Tips: The product may be updated constantly , Due To Different Batches, The Actual Product May Have Slight Differences Or Color Differences, Which Does Not Affect Use Material: Metal colour: Black Package Contents: 1 x Lens Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is 1-3cm.