Vortex Ballistic Rifle Rangefinder

From the Amazon Listing

• Rugged & reliable, the Impact 4 takes the guesswork out of long-range shooting with quick, accurate ballistic corrections using the easy-to-read display from your shooting position. Pair via Bluetooth with your phone on the GeoBallistics app.
• The rail-mounted Impact 4 delivers key range, ballistics, and weather data via the integrated GeoBallistics solver, on-board environmental sensors (compass, humidity, barometric pressure, and temperature sensors), and Wind Bearing Capture Mode.
• GeoBallistics is a ballistics solver with a full, up-to-date database. The Impact has a Built-in range card generator to store up to 1 range cards. The Vortex Relay Network provides seamless connection to the GeoBallistics app and Bluetooth remote.
• Use the patented Wind Bearing Capture Mode to manually input wind speed and direction for accurate wind corrections on targets. The Impact will keep track of wind direction regardless of the direction the user is facing.
• Using a rail-mounted design, mount the Impact using the Vortex Precision Diving Board to any Vortex Precision Rings, Precision Cantilever Mounts or picatinny rail section. The Impact is watertight, and shockproof for confident performance in the field.
• Backed by our unlimited, unconditional, lifetime, VIP Warranty. A fully transferable promise to repair or replace your item if it becomes damaged/defective. Does not cover loss, theft, deliberate damage or cosmetic damage that doesn't hinder performance.