1740 Series readers and version 4.5.0 are 100% backward compatible in most applications where In-Sight 1720 Series readers are currently being used. However, there are many new features and other changes that 1720 Series users should be aware of when making the transition to the 1740 series, or when upgrading 1720 Series readers to 4.5.0 from an earlier version. Also, users who control the wafer reader from a custom application should be aware of several new and/or extended Native Mode commands.