Match it with child from the 1.5 year old time and is the toothbrush which balanced "a washing effect" with "the gentleness to a mouth". 

Practice for yourself. 
You can practice removing food stains from the age of one year and six months when the back teeth start to align. 

There are two types of brush hairs: high-washing hair and soft, non-abrasive hair. 
Remove dirt from the back teeth grooves and gaps firmly. 

A straight handle with non-slip grip that you can take it by yourself.