TIETwainParams.DuplexSupported
 
Declaration
property DuplexSupported: boolean;
Description
If DuplexSupported is True, the scanner can scan both sides of pages. Otherwise the scanner will scan only one side (CAP_DUPLEX).
Also see: 
DuplexEnabled
Twain Properties: CAP_DUPLEX
Note:
◼Use 
IsCapabilitySupported to determine if this capability is supported by the current scanner
◼This property is affected by the 
Twain Compatibility option: 
ietcExplicitlySetCapabilities
// Enable duplex if supported
If ImageEnMView1.MIO.TwainParams.DuplexSupported then
  ImageEnView1.IO.TwainParams.DuplexEnabled := True;