Thank you for your question!
Each component you equip onto your club is part of a Set and is represented by a letter in their icon. For example the Energy set with the letter E, if you equip four components that are part of the Energy set, that club will receive a +30 Strength bonus!
Please see our Solution article "How Do Club Component Work?" for a breakdown of every set type.
I hope this helps, if you have any other questions, please let us know.
See you on the course!
PS: Check out our Youtube tutorial Video Stats and Components for more info on all the set effects with examples of how they influence the game!