As an additional note, you may also add markup language for pausing or waiting, I learned this from the iPhone iOS which allows numbers to be stored with extension numbers in the same line. A semi-colon establishes a wait, which will show as a next step upon calling the number. This helps to simplify the workflow of calling numbers with extensions in their board. You press the button shown on the bottom left of the iPhone screen when prompted, and the iPhone will dial it automatically.
<a href="tel:+50225079227;1">Call Now</a>
The pause is entered with a comma ",", allowing a short pause of time for each comma. Once the time has passed, the number after the comma will be dialed automatically
<a href="tel:+50225079227,1">Call Now, you will be automaticlaly transferred</a>