About Product:Detect the Simple Reaction of People to the Change of Things, That Is, the Time When the Index Finger Leaves the "Start" Key.B. Detect the Comprehensive Response of People to the Change of Things, That Is, the Time When the Signal Is Sent to Press the Key with the Corresponding Light on.Technical ParametersTest Range: 0-9.999 SecondsB. Dividing Value: 0 001 SecondsStandard RS-232 Communication Interface (Nine-Core Socket)CiD. Power Source 220V,50HzDuring the Test, the Average Values of the Simple Reaction Time and the Comprehensive Reaction Time Are Displayed Respectively for 5 Consecutive Tests.