The problem you have encountered is quite strange. Please provide a more detailed description of the setup that causes the described behavior. Is the bigger size applied only to the RadButtons or to the standard Button controls and the button input elements on your page?
It is possible that the custom CSS styles of your page are causing the strange appearance. To check if this is the case, you can remove the custom styles.
You can also include a screenshot that displays the buttons so that I can examine then on my end.
the Telerik team
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