Request a call button for wordpress site?

Hi.

Please can you mark this post as private.

I want to have a "request a call" button on the homepage of my website that looks and has the same functionality as the one shown on the top right hand side of this website:-

http://www.octavedigital.co.uk/digital-marketing/social-media-marketing/?gclid=COaylLyIl7sCFTDMtAodLEwASg

Can you recommend me a good one or do you know hat this one is as it looks great in my opinion.

Thank you