Interfit RF5003 Standard Reflector Stellar Fit Description. This Interfit Spill Kill reflector produces a wider spread of light ideally suited for use with all types of lighting umbrellas. A 1cm hole in the reflector is provided to accommodate the umbrella shaft. This reflector is supplied with all Interfit Combo Flash & Halogen Units but will also fit Bowens flash units. The outer rim of the reflector is designed to hold the Interfit Pro Honeycombs without the need for a further adapter.