Will this power2max power meter be compatible with Cannondale Synapse?
Yes, you can install a Type S - Rotor 3D24 on your Synapse using the following adapter:

https://www.c-bear.com/en/products/bb30a-cannondale-synapse

You also have the option of Type S - FSA MegaExo (Gossamer or K-Force Light) and Type S - FSA BB386EVO (Gossamer or K-Force Light). Please have a look at the following chart from FSA:

http://www.fullspeedahead.com/wp-content/uploads/2014/04/POSTER-BB-2014-ROAD-A234.pdf

If you have any other question, please feel fre to ask !

Andrés
power2max Team