This speedring insert is a replacement part for EZ-Pro DLX Softboxes. By replacing the insert with a different model, you can mount the light modifier on almost any strobe or light, allowing you to expand your lighting options or use the same modifiers for multiple setups.Compatibility: Bowens & Compatible Lights - Popular models include: Bowens Gemini Calumet Travelite Interfit (S1, Stellar, X, XD, Stellar Extreme, Venus) Neewer (DS & GS) Westcott (Skylux, Strobelite Plus) Flashpoint I Impact brand (VC, VS & VSD) PhotoflexNote: Does NOT fit standard softboxes, regular EZ-Pro softboxes or beauty dishes. Only works with EZ-Pro DLX Softboxes.