dhtmlxCombo can be used in four modes:
Since version 4.0, dhtmlxCombo has been overwritten to provide faster loading, better performance, and more customization options. It now supports easy creation of linked combo boxes, sorting, custom text templates, and multiline items.
dhtmlxCombo is available in the Standard Edition only. Download and use dhtmlxCombo for free under GNU GPL, or buy a Commercial or Enterprise License to use the component in a non-GPL application/site and get official support.
Commercial License ($49) - Allows you to use dhtmlxCombo Standard Edition in one project (application) with an unlimited number of copies. The license includes 1 month of technical support (or 5 support requests within 12 months) and one major update. Buy it
Enterprise License ($99) - Allows you to use dhtmlxCombo Standard Edition in an unlimited number of projects on the condition that all of them are developed by one company. Free support/upgrades are provided for the first 12 months. Buy it
dhtmlxCombo Standard Edition is distributed under GPL v2, Commercial, and Enterprise licenses (details)