Kaisi K-858D SMD Hot-Air Soldering Station LED Digital Display Support Controllable Temperature for Desoldering + Air Nozzles, US Plug1. Closed loop sensor, temperature controlled by microcomputer and LED display which lead to steady and accurate temperature. It makes the non lead desoldering come true 2. The air flow rate is adjustable, the air volume is large and gentle, the temperature can be adjustable easily, widely applicable 3. There is a sensor switch in the handle, the system enters the work mode as long as you hold the handle, and it enters the standby mode when the