Jefftron Leviathan V2 Optical Computerized AEG Trigger Board (Bluetooth)Trigger included. The Leviathan V2 optical is one of the most advanced ETU (electronic trigger unit) on the market It combines optical and switch sensors for better handling and durability Built in wireless communication for quick setup using iOS or Android smartphones! Tactile trigger switch has travel only 0,13mm long for ultimate hair trigger feeling You can choose from 10 types CNC triggers with screw to adjust trigger travel Unique Real feel