The insulin pump device used throughout the clinical validation is the Roche Accu-Check Combo Spirit. This is a CE marked MHRA approved device and will be supplied by Roche with capability for direct communication from the motor so that we can verify the pump is doing what the software commands and with a license to use the communications protocol for research purposes. This ensures safe communication between the control algorithm and the pump and provides a fail-safe to ensure that the pump motor is responding appropriately to the control algorithm.