MOT rules and regulations state: 1.2: Headlights A pair of headlights must: emit light of substantially the same colour and intensity. Emit a steady colour of either white or yellow. be visible from a reasonable distance. 1.3: Brake lights A brake light must emit a steady red light. At least 50% of the lamp must be visible from the rear Light must be visible from a reasonable distance 1.4: Reflectors At least 50% of the reflecting surface must be visible from a reasonable distance. 1.5: Indicators Every indicator must emit amber light. At least 50% of the lamp must be visible. Light must be visible from a reasonable diqstance. Masks, or converter kits. A headlamp or rear tail lamp altered in this way is not a reason for MOT rejection. So long as light outputs are not adversely reduced, it emits the appropriate correct colour and the mask is securely. Please note that high-intensity discharge light bulbs (H.I.D/Xenon) may cause excessive heat build-up under sustained high beam use. This may result in melting of the vinyl.