Osram Vialox NAV-T 400W SUPER 4Y E40

By purchasing the quantity recommended, your products will come as packaged by the manufacturer.

The cap/base of a bulb is the part that connects it to the socket in the fixture. E27 (Edison screw) and E24 (small Edison screw) caps/bases are among the most popular, although this depends on your location. GU10 is generally the most common cap/base for spotlights. Check which cap/base you need carefully as many other types are also available.

The colour temperature refers to the colour produced by a light. It's measured in Kelvin (K) and ranges from warm white (1700K - 3000K) to daylight white (6500K). Neutral white (3100K - 5000K) is mainly used for general lighting applications.

The colour code is a combination of the colour rendering index (CRI) and the colour temperature (K). The first number refers to the CRI (1 = very poor colour rendering, 9 = maximum accuracy). The second and third numbers refer to the colour temperature. For example, a light with a colour code of 830 has very good colour rendering and produces a warm white light.

The colour rendering index (CRI) indicates how accurately colours are represented under a beam of light. The index goes from 1 to 99, with a CRI of 1 being the poorest and a CRI of 99 being the best possible. Be careful not to confuse colour rendering with colour temperature (K).

Lumen (lm) is the term used to describe the total amount of visible light emitted by a light source. The higher the number of lumens, the brighter it is.