Quattro audible altimeter Four high-speed warnings: Allows settings up to 19990 Feet and can be used for Bigway formations, wingsuit flight setup and other precision skydives where four high-speed warnings are needed and desired Track Guide: 0.5 second pulsating tones between the 1st and 2nd warnings help keep track of altitude separation of tracking groups or waves Long lasting, easy to find batteries Three canopy descent and low speed warnings: The Canopy Descent Alerts are essentially low speed alerts and can also be used by wingsuit flyers to keep track of altitude in preparation for separation and canopy deployment The QUATTRO is specifically designed for advanced skydiving disciplines: Bigways, Formation Skydiving, Freeflying, Wingsuit Flying, Student, Tandem, AFF, and also canopy related activities such as accuracy and CRW