RadControls for ASP.NET AJAX 
XHTML 1.1
RadTabStrip “for ASP.NET Ajax” is compliant with the XHTML 1.1 requirement.
Section 508
RadTabStrip satisfies the requirements of "Section 508" for software accessibility, as well as those of "Level AAA" (in accordance with the W3C Web Accessibility Guidelines 1.0).
See Also