Featuring the dB-Mag Roller with 8 magnets and ISM (Intelli-Sense Mode), false indications are eliminated in extreme conditions. The SRT (Sync-connect Receiver Technology) optimizes signal strength, and the Tru-tone cone speaker delivers loud frequency. With a range of advanced features, these alarms are designed to meet the demands of serious anglers. Upgrade your angling experience with Trakker's advanced technology. dB7-R Alarm SetPPS (Power-On Protection System)  ISM (Intelli-Sense Mode)  dB-Mag Roller with 8 precision magnets  Tough ABS weatherproofed case  Digital circuitry and internal weatherproofing  SRT (Sync-Connect Receiver Technology) Tru-tone cone speaker  Dual-descent tone drop-back differential  Dual super-bright multi-colour LEDs  One-touch night light function  Rod-friendly rubber inlay grips  Rigid 3/8" stainless steel thread  Requires 1 x PP3 9V battery  Dimensions: 11.2 (L) x 5.4 (W) x 4.5 (H) cm  Weight: 98g  dB7-R ReceiverPPS (Power-On Protection System)  Tough ABS weatherproofed case  Digital circuitry and internal weatherproofing  SRT (Sync-Connect Receiver Technology)  Connect and update up to 16 alarms  Tru-tone cone speaker  D-Vibe vibration setting  LER (Last Event Recall)  Indexed volume control wheel  Low battery warning  Self-standing case design  Requires 1 x PP3 9V battery  Dimensions: 9.2 (L) x 5.4 (W) x 4.5 (H) cm  Weight: 72g _