Perhaps, you may know since Q3 2011 RadInput has a new rendering mode. Now the RadInput form controls use a only one input of type text to keep the entered values. Whereas with the non-single input rendering mode, two or three inputs of type text are rendered.
However, now the RadInput has CSS 3 property box-sizing
and the padding and borders are not added anymore to the dimensions as in the common box-model.
For example, if you set Height="15px" (or with CSS) to the input, it will be exactly 15px, not 22px (5px padding + 2px borders) as in the old rendering.
Additionally, in case you did not set the height, it will be exactly as before (non-single rendering).
I hope this helps.
the Telerik team
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