DescriptionMultifunction button,press shortly to open/closebacklight,press it for 3 seconds to change bodymode to object modeor object mode to body modeMultifunction button,press shorly to urn onloff beeperMultifunction buton,uses with button 1 and button 2.press it shortly to inquiry memory data,press testing button to exitpress it for 3 seconds,it enters in advanced setting.uses with button 1and button 2 as part7.