Refraction of the 650nm red light caused by any breaks and or cracks in the fiber will glow red, thus giving an exact visual location of the fault in the fiber.

Features:

• 2.5mm Adapter built into unit(ST, SC, FC connector)
• 1.25mm adapter availabe to purchase seperatly (this adapter is shown in picture)
• Robust and handy design
• Dust-free cup to protect LD
• Continuous/Pulse mode options 
• Emitting LD 650 nm visible red light
• Low voltage battery warning signal in led