Specifications: Product Name: DT01 Version: 10-30X21 Multiplication rate: 10-30X infinitely variable Objective lens diameter: 21mm Eyepiece diameter: 12mm Field of view range: 1.6 °/30x3.3 °/10X Lens: XP 5-circle lens Prism: BAK-4 Coating: FMC multi-layer broadband green film Pupil exit distance: 14-12mm Product Size : 13 * 3.5 * 3.5cm Product Weight : 78g