Base, Shape And Dimensions Base: G4 2-Pin Bi-Pin With 4Mm Pin Distance Shape: T3 Tubular Jc Type Diameter: 0.375 Inches Length: 1.19 Inches Please Make Sure The Light Bulb Base Matches What Your Light Fixture Has. Lighting Features Power: 20 Watts Luminous Flux: 240 Lumens Voltage: 12 Volts Ac Or Dc Beam Angle: 360 Material: Glass Color Rendering Index (Cri): 100 For Vivid And Enhanced Color ,Instant On. No Mercury. Lifetime: 2,000 Hours (1.8 Years With Average Of 3 Hours Use Per Day) Ce And Rohs Certified Pack Of 10 Working With Halogen Dimmers These Halogen Light Bulbs Are Dimmable Using The Dimmers Designed For Incandescent & Halogen Light Bulbs. All Incandescent And Halogen Light Bulbs Are Dimmable Using Traditional Dimmers, As These Dimmers Simply Adjusts The Voltage Level For Dimming. Dimming Using Led Only Dimmers Will Result In Incompatibility, As Led Dimmers Work Very Differently. Please Check The Compatibility Of Your Dimmer Switch Or Light Fixture Prior To Purchase.