Cuticle nippers come in many different styles. We see variations in all aspects of their design, from handles to colour to textures and so on. But by far, the most widely-used method of holding the cutting jaws apart and creating tension, is by using springs. They are a simple, elegant way to achieve that perfect amount of resistance and control.
There are typically two styles of springs: Single (left) and Double. And the best way to communicate the difference would be to show you what they look like.
The single spring consists of one thin, bendable piece of stainless steel, with one end attached by a screw to the inner handle, and the other end touching the opposite handle. In this position, the jaws are open and ready to be used. With the handles snug in your palm, squeeze them firmly but gently. You don't need to apply a lot of force if your cuticle nippers are sharp. When you are done for the day, you can choose to swivel the spring to release contact with the opposite handle and close the jaws. Be sure to pull the protective cap over the sharp jaws to keep the nippers safe from damage. Do not jam the cap on too tightly.
The double spring fulfills the same function, but consists of two pieces of stainless steel instead. They each are connected to opposite handles with screws, and are clasped together to create the tension needed to hold the jaws apart. Most users simply pull the protective caps over the jaws of these double spring cuticle nippers when they are ready to be stored. But you can also pop the clasp and swivel both springs to point downwards, before storing. It's a matter of preference.
Some users prefer the single spring because it tends to have less tension and thus makes it easier to squeeze the handles and make multiple nips quickly. In fact, certain users even go as far as to have the spring removed altogether, although I would only recommend that if you are an experienced manicurist.
Fans of the double spring nippers say they like it because it offers more control and stability. That stability comes from the way that the springs are screwed on to both handles and then clasped, effectively joining the handles together as one unit. This type of nipper might be more suited towards users with larger hands, because the double springs generally keep the handles further apart. If you are new to such tools, I recommend that you try the double spring 5mm jaw cuticle nippers.
Nail-beauty tools come in many variations and the best way to find out what suits you best is by experimenting. Feel free to ask us for recommendations. Enjoy!