Believe your skills, abilities and experience (education, etc) are a good fit with this particular position.
****Because your talents, skills, experience DO match the job specs****
Also mention the all the positive aspects about the company (financially, etc) and its good reputation and history within the industry (whatever the industry).
***you know this because you googled the company and read up on it BEFORE the interview and it's a decent, solid company. If it were NOT a solid company, you wouldn't be interesting in working there anyway and you wouldn't be on this interview...right? Right.****