The MeiKe GT-600 (or MK-GT600) is a 2.4GHz wireless flash triggering system made up of low-profile transmitter and receivers. The transmitter has a top-facing LCD control panel allowing adjustment of up to three groups of off-camera flashes. You can use them in TTL or manual mode.
With all the buttons and dials on top of the trigger, like on the Yongnuo YN-622N-TX there is no room for a TTL pass-through hotshoe, in case you wanted to use an on-camera flash at the same time. Nonetheless MeiKe do fit a decent number of features into a small package, including a PC sync port, decent-sized screen, high-speed sync, remote zoom control and full group adjustment.