Tubular or 'capsule' metal halide bulbs are used in all types of commercial lighting ranging from shop displays to street lights. The small size and very high output combined with a long life and great colour temperature makes them a popular choice. Often supplied with a G12 lamp cap where the pins are 12mm apart.
Linear metal halide bulbs are often used in commercial display lighting, usually in 'flood' type light fittings. They provide a lot of light in a small package. Often used when lighting large areas where a wide spread of light is required.