I installed the off road thumb trigger kit to my NCM Prague. It came with very clear instruction in the box however the passcode in the instructions said enter code 8018. I eventually read the instructions on line. It said use code 8088. Finally I was able to get in and set it up correctly. I accept it was my own fault. If all else fails read the instructions. ( but which one?) I purchased the kit because I had two knee replacements. It allows me to get back from my ride if I go beyond my capability. I can not be happier with my purchase. The trigger gives very controlled acceleration to around 30km/h without the need to peddle if required. Its great to be mobile again. Thanks Leon Cycles. Service and delivery times were excellent.