The Rigid Scope – 4mm from USA Borescopes is a Borescope with Viewing Angle 30 Degree, 70 Degree, 90 Degree, 110 Degree, Field of View(FOV) 65 Degree, Operating Temperature 80 Degree C, Probe / Insertion Tube Diameter 4 mm, Probe / Insertion Tube Length 175 mm, 302 mm, 430 mm. More details for Rigid Scope – 4mm can be seen below.