Clenbuterol has become very popular especially among those people who have been struggling with their overweight issues. If the name this drug may sound pretty unfamiliar to your ears, the size zero pill might trigger your memory to recognize this anabolic drug. Size zero pill is actually the popular brand or name for clenbuterol. It has been well known for its great help to our weight loss programs. These days, we have been very familiar with a modern lifestyle that leads us to suffering from serious health issues including obesity.