
There are 2 types of handles for Curling Irons:
Spring Type - means that you will use your thumb to open the iron, and a spring will close the iron. Spring type irons are normally found in the home.
Marcel Type - means that your hand will close and open the iron. There is no spring to cause the iron to close. Your hand controls the pressure on the hair. Marcel irons are used by professionals in a Salon since it is more versatile when working with the hair.
This webpage lists SPRING handle curling irons: