IEC TS 62965:2016 which is a Technical Specification, specifies a minimum set of dimensional requirements for fusion splice on connectors (FSOCs) ferrule assemblies and the interface dimensions of splicing tools to ensure that a compliant ferrule assembly is compatible with a compliant fusion splicer. This fusion splicer interface also provides an example of the dimensional requirements for a universal holder, into which an FSOC can be mounted. This fusion splicer interface applies to FSOCs with a cylindrical ferrule of 2,5 mm diameter or 1,25 mm diameter.Keywords: FSOC, fusion splicer interface