Type: Energy Saving Bulb 16W 4 Pin Base compatibility: 16w 4-PIN CFL lamps - PLEASE CHECK YOU REQUIRE A 4-PIN GR10q BASE FITTING CAREFULLY Colour and brightness: Cool White - 3500K Kelvin - 28w / 2000+ Lumen / High Efficient Tri-phosphor Coating With Excellent Colour Rendering Shape: Square Shape Provides Uniform Distribution Of Light Key benefits - Energy efficient replacement for compatible 4-pin CFL fixtures - Square shape delivers uniform light distribution and reduces shadows - Cool white 3500K with high lumen output and good colour rendering for clear visibility Specifications and compatibility - Type of bulb: Energy Saving Bulb 16W 4 Pin - Base: 4-pin CFL (GR10q). Please verify your fixture requires this base Use scenarios - Office ceilings with 4-pin GR10q fixtures such as troffers and panels - Retail displays and showrooms needing bright, true-colour illumination - Kitchens, workshops, or classrooms using compatible square light fixtures