The X-30 from Shanghai Shinho Fiber Communication is a Optical Time Domain Reflectometer (OTDR) with OTDR Measurement Time 15 seconds to 3 minutes, Event Dead Zone 1.8 m, Attenuation Dead Zone 10 m, Optical Wavelength 1310 to 1550 nm, Dynamic Range 28 to 30 dB. More details for X-30 can be seen below.