This part of IEC 63356 specifies design parameters and design values of a LED light source or related interface characteristics. Note 1: Interface characteristics can cover interfaces between LED light source and luminaire/controlgear or LED light source and additional attachments. Note 2: Interfaces can be related to for example electrical, mechanical, or optical aspects. This part does not cover interchangeability between products from different LED light source manufacturers. Note 3: Interchangeability is covered by Part 1. Lamp caps and lampholders specified in the IEC 60061 series are not in the scope of this document. Compliance criteria relating to parameters in this document are covered by IEC 63220 for safety, or IEC 63221 for performance.