1、MAXIMUM APERTURE: Manual focusing prime lens has maximum aperture f1.7. Helps you achieve background bokeh effect and increase the brightness of images in dark environments 2、EXCELLENT PERFORMANCE: 35mm F1.7 manual focusing prime lens features an alloy housing and excellent lens that performs well and is resistant to damage 3、ADVANCED OPTICAL TECHNOLOGY: F1.7 manual focusing prime lens uses advanced optics to ensure all around clarity and effective light guidance 4、MANUALLY ADJUSTABLE APERTURE: The aperture of manual focusing industrial lens is manually adjusted according to the available aperture. Exquisite workmanship, you can put the lens in your pocket 5、APPLICABLE SCENARIO: Manual focusing camera lens is suitable for all kinds of photography, including landscape, portrait, still life, travel, wedding Item Type: Manual Focusing Prime Lens Model: 23SM3517C Material: Aluminum alloy Resolution: Standard series Sensor Size: 2/3in Focusing Length: Approx. 35mm / 1.38in Aperture: F1.7 Mount: C mount Distortion: 2.0% Flange Back Focusing Length: Approx. 17.526mm / 0.69in Optical Back Focusing Length: Approx. 9.3mm / 0.37in Mechanical Back Focusing Length: Approx. 17.5mm / 0.69in Aperture Control: Manual Focusing Control: Manual Operating Temperature: -20℃ to +60℃ 1 x Manual Focusing Prime Lens