Each STREX instrument comes with a Controller that is programmed with strain parameters for easy and convenient use. It is designed and built for intuitive use - no complicated or time consuming directions to follow. Just plug it in and use it. The Control Unit is programmed to run up to 168 strain parameters. Refer to Instrument Dimensions to view the preprogrammed strain parameters for each STREX model. If you prefer customized strain parameters, we can do that too!