The F1 alarm with built-in signal transmitter features a timeless design and is made from extremely durable materials. Enhanced rain resistance is ensured by perimeter sealing. The revolutionary line detection type allows for very fine adjustments starting from 1.4 mm with sensitivity regulation up to 14 cm. The spool that detects line unwinding is equipped with a metal axle, preventing wear and ensuring smooth operation. Simple and intuitive control is provided by a toggle switch located at the bottom of the alarm. The angler can set the RGB LED colors and adjust the brightness intensity of the LEDs. There is also a MUTE function, a connector for attaching a swinger, a position LED (which can be turned off), and most importantly, optical and sound differentiation of the bite direction (drop). The alarm is powered by standard LR03 (AAA) batteries, eliminating the worry of sourcing expensive atypical batteries. The batteries are also very easy to replace by simply unscrewing the bottom nut and releasing the battery cover. The signal transmitter is very powerful, with a range of up to 1.5 km. The RFX receiver has 6 channels for connecting alarms and security sensors.