This Ultra Thin HQ Borescope is one of the best option for extremely small inspection areas. The diameter of the probe is only 0.5 mm. This object provides a brilliant, high resolution image. A focus ring is built into the hand piece of the scope. The advanced image bundle is composed of 3000 densely-packed microscopic quartz fibers. These fibers are small enough to provide a brilliant high resolution image but not too small to leak out some light. The fibroscope also includes a portable LED light handle, to illuminate the inspection area directly from the tip of the insertion probe.