Garmin HRM 3-SS will connect/pair with forerunner 35 but will not show heart rate (see picture) - Accessories & Sensors - Running/Multisport - Garmin Forums
Everything you ever wanted to know about the Garmin HRM-RUN | DC Rainmaker
Support: Using a Garmin Heart Rate Monitor - YouTube
Garmin HRM-Dual | ANT+® and Bluetooth® Heart Rate Monitor
Garmin HRM-Dual | ANT+® and Bluetooth® Heart Rate Monitor