CCTV Lens Range Calculators
Front to back: 

It is a book-like construction with an interactive wheel sandwiched between front and back covers. Add a cover and bind in additional pages and you've created a booklet style chart that will be attention-getting and memorable.

A Trapped Dial's user-friendly design helps overcome customer resistance to complex information.

  

 

Round wheel chart calculators remain popular with engineers, medical professionals, educators and scientists.




Wheel chart calculators are also known as circular slide rules... compu-wheels... graphic calculators... spin guides... whiz wheels... wheel charts