Velo or the LINK?
Both devices measure heart rate from the wrist and transmit via Bluetooth 4.0 and ANT+, but only VELO is able to bridge ANT+ sensors to Bluetooth 4.0.
The VELO wristband is blue, while the LINK wristband in available in arctic, slate, or electric yellow.
It depends on how you want to use it. If you don’t need to bridge ANT+ bike sensors to your smartphone, just get LINK.