Since Q3 2011 RadInput has a new rendering mode. This mode is controlled through the EnableSingleInputRendering property. Since Q1 2012 it is set to true by default and the RadInput controls use a single 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.
Enabling the single input rendering mode improves the page performance and allows for easier customizations.
However, you can control the width of the RadInput control with the property Width or with the following CSS rule
For more information please refer to the following help topics
I hope this helps. Please let me know if I can assist you any further.
the Telerik team
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