... competitive price,superior service advanced testing equipment quick delivery tern Air flow meter (Good quality,low price) Specifications:A,SBL digital ... ,304,316(can offer according to customer's need)Power supply:Built-in 3.6N li batter,(lifetime 1~2 years ... ),external power supply of 24VDCOutput forms:4-20mA;pulse,0-10V;RS232/RS485 ...