Extech sdl310 vane thermo anemometer datalogger extech sdl310 the extech sdl310 vane thermo anemometer and data logger records data on an sd card in microsoft excel reg format for easy transfer to a pc for analysis the user can manually store 99 readings or set the logger to automatically store up to 20m samples with date and time stamp at a user selected sample rate the vanes withstand temperatures to 50 deg c 122 deg f and air velocity to 25m sec 4930ft minute complete with 6 x aa b