The B+ series from Yateks is a Borescope with Depth of Field(DOF) 3 to 50 mm, 5 to 50 mm, Viewing Angle 120 Degree, Probe / Insertion Tube Temperature -10 to 60 Degree C, Operating Temperature -10 to 50 Degree C (System), Probe / Insertion Tube Diameter 2.2 to 3 mm. More details for B+ series can be seen below.