The Freelap Tx Touch Pro transmitter can be used for block starts and four-point starts. The transmitter is compatible with both the FxChip and FxChip BLE. The transmitter is placed on the start line. The athlete presses the button with their thumb. As the athlete begins to sprint, their thumb releases the button, and the transmitter emits a magnetic pulse that resets the internal timer of the chip they are wearing to zero.