Submarine periscope | American Military Stand MIL-PRF-13830B Industry Standard, Surface Quality (60-40)(40-20)(20-10), Eco-Friendly. High Tolerance, Anti-Reflection Coating, Most Cost-Effective Optical Solution. Choose Now. Quality assurance. Per www.jinyioptics.com/product/periscope Submarine periscope | American Military Stand MIL-PRF-13830B Industry Standard, Surface Quality (60-40)(40-20)(20-10), Eco-Friendly. High Tolerance, Anti-Reflection Coating, Most Cost-Effective Optical Solution. Choose Now. Quality assurance. Per www.jinyioptics.com/ |