Technical Features SP02 Measurement range: 30~99% Accuracy : ±1% for 70-99% Unspecified for 0~69% Alarm Range: 0-100% Pulse Rate Range: 30-255 Bpm Accuracy: ±1% or ±1 Bpm [Select Larger] OPTIONAL: Wireless Communication for FTP 401 Product Description Rechargeable lithium battery with charger Audio and Visual Alarm Software to interface with PC [throughUSB] [Only for FTP 401] Color OLED Graphic Display True color OLED with 4 Direction Display Battery Voltage Indication Color OLED Graph