RFID PocketWork HF for Series 21D Pressure Transponders. The small handheld reader is used to provide a real-time display from the Series 21D pressure transponders. In SPC mode, the reader will function autonomously and display instantaneous values on the OLED display from a Series 21D pressure transponder. The PocketWork HF will log the sensors individual MNR, pressure and temperature readings. 23,500 readings can be stored on the unit from multiple different transponders. In DOC mode, this reader will function in the same way as the PENmini and will send data directly to a PC. The reader has a built-in rechargeable battery with USB recharging.