200 GHz demux for C-band. With 21 LC/PC fiber connectors, and 10pc duplex LC adapters (see 1st photo). They were removed from exactly same Lucent 40-ch DWDM C-band system model (see last 4 photos below). The frequency (wavelength) data is printed on the front of the DWDM system, 9580 means 195.80 THz frequency (1531.12nm), 9200 means 192.00 THz frequency (1561.42nm). In this 1531.12nm - 1561.42nm DWDM system, input 100GHz-spaced signals pass through the  interleaver  firstly, one output is 200GHz-spaced odd-channel signal, the other output is 200GHz-spaced even-channel signals. The even-channel signals pass through this 1x20 200GHz demux. With model number, but no datasheet or test sheet due to discontinued products. This NTT model: AWG1620SHM(DEMUX200-10) has same performance as Hitachi model: HSGW-6512-LD01 (Store product code: FFC-MUX-017C), since either of these demux is found in the same Lucent 40-ch DWDM C-band system model.

Sample was tested locking at ITU grid with temperature controller. We verified that pinout info is same as the 2nd pdf link below. Basically you need connect two heater pins and one pair of RTD temperature-sensor pins to your temperature controller (many types of temperature controllers support RTD temperature sensor). Then you can easily set demux to required temperature (about 70 C).