The San Francisco 49ers signed quarterback Colin Kaepernick to a six-year, $126 million contract extension in June.

Why did Kaepernick agree to a team-friendly deal? How does he deal with critics who say that he isn't worthy of an extension fit for a franchise QB? What's it like playing QB under intense head coach Jim Harbaugh?

Watch as Kaepernick and Bleacher Report NFL Analyst Chris Simms go in-depth at 49ers training camp in the video above.