This Tool is a frequency sweeper with 5V square wave output (Duty cycle 50%, effective frequency range from over 10kHz (max 50kHz) to 50Hz). This tool can be also considered as a MCU version of the software TMS-374 Decoder ECU. The only difference between the two tools is that the MCU version works without a PC. A small MCU is used to generate the pulses instead of the PC RS232 Tx line. TMS374 ECU DECODER:A handy tool to have that decode an all the above ecu's to a state without the need of a laptop! Colour:As Shown Material:PC Due to different batches, there may be differences in product appearance and printed text, which not affect use Package Contents: 1 * TMS 374 ECU DECODER Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.