CM4318/3-T Specifications: Focal Length: 4. 3mm F. No.: 1. 8 F. A. Diagonal: 83. 2? M. O. D.: 0. 2m Format: 1/3" Mount: M12?0. 5 Dimension: Φ 14?14. 75mm Weight: 6. 0g We produce IR board lenses with focal length 3. 6mm/4. 3mm/6. 0mm/8. 5mm/12. 5mm/16mm/25mm, and F No. 1. 6 or 1. 8. More infomation please contact me via email. Chikon series lenses are famous for best quality and satisfied services in China, even around the world. Being a professional manufacturer, we are not only aware of keeping advanced optical technology, but also the best service for our overseas clients. When you contact us, you will find out our sales reps are more easy to communicate and more professional in products and optical knowledge. Hope you'll enjoy your purchase travel here in Fujian Institute of Optical Technology!