GY6.35 bulbs are low voltage halogen capsule bulbs, but generally run at a much higher wattage than G4 bulbs.

Like a G4 bulb, GY6.35 bulbs also have two (often sharp) pins at the base but as their name suggests they are further apart at 6.35mm.

The higher wattage versions of these bulbs are often used in specialist applications such as projectors and stage lighting.