The Wahoo Key connects your iPhone 4S to any ANT+ fitness sensor such as heart rate monitors, cycling speed & cadence sensors and power meters so that you are able to pull data into an iPhone app.

Specs:

• Part Number: WFFISICA01
• Wireless ANT+ AP2 ultra low power technology license free, 2.4 GHz ISM band operation
• Weight: 3.5 grams (0.12 ounces)
• Color: Black
• Signal Strength: Up to 10 feet unobstructed