The RadFormDecorator needs to change the markup like this in order to provide the consistent styling of the elements. The rfdRealInput is a class added so we can easily obtain the actual element, e.g.:
boxes = $telerik.$(
".dynamicChecboxes > .rfdRealInput"
where dynamicChecboxes is the class added when they were created.
For your convenience I am attaching a simple page that shows this in action. I hope this helps.
the Telerik team
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