Fish can be pretty finicky or picky when it comes to being ready to be caught. The right temperature and speed are key some days. This sensor will measure just that. Providing digital speed and temperature readings, as you glide through the water, you can sensor your fishing trip according to your fish&';s mobility. Ensure you catch the big one next time, with this transom mounted sensor. WARNING: This product can expose you to chemicals including Lead and Lead Compounds, which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information, go to: www.P65Warnings.ca.gov Combines two of the most popular accessory inputs into one Compact Transom Mount Unit 20 feet of Cable Hardware Included Temperature Range: 25-99.9Adeg F Speed Range: 2-75 Mph If you just bought a new unit, please verify your unit does not come with this sensor, as many now do Compatible with over 134 models