Use the below template for a simple, professional hand-written thank you letter. You don't want to say the wrong thing, and what's most important is the fact that you send it. Template below:

“Dear ____
 
Thank you for your time and insight into this (insert name of role here) role.
 
After getting to know you, the team, and this mission here at (insert company name here), I am convinced that my experience in (insert your area of expertise here) will help advance your mission.
 
Sincerely,
Your Name”
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