The H15 bulb is a combination solution. It has two filaments:

15W: used for daytime running lights (DRL) or parking lights.

55W: used for high beams.

Strengths: The "white effect" is the main selling point for buyers. Stock bulbs often produce a yellowish light that looks cheap. White light gives the car a more modern look and better illuminates road signs and markings.

Weaknesses: Halogen bulbs with a "white" coating have a slightly shorter lifespan and may be less effective in heavy rain or fog (due to the color temperature).

Opportunities: This is a great product for cross-selling. If a customer is looking for H15 bulbs, they'll likely soon need bulbs for their fog lights or low beams to match their color.

Threats: Competition from LED alternatives. However, many customers are concerned about traffic police issues or trip computer problems (check lamp errors), so high-quality H15 halogen bulbs remain a popular and safe choice.