Convertible multi-diameter sleeve for optical fiber connectors

A convertible multi-diameter sleeve for optical fiber connectors which connects optical fiber cables using plug ferrules of different outer diameters by pushing said cables into said sleeve while maintaining precise core alignment, said sleeve comprising:

• a left portion having a left end and a right portion having a right end, both said left and right portions having a cylindrical shape and are located on a single axis with respect to each other and said left and right portions have different inner and outer diameters;
• and
• a taper shaped diameter change portion between said left and right portions,
• wherein a first member is selected from a group consisting of the left portion and the right portion, wherein said first member has a larger inner diameter and a larger outer diameter than an other member of said group, and the other member of said group has a smaller inner diameter and a smaller outer diameter than said first member;
• wherein provided radially with regular intervals on said first member are at least three slots having a length of at least 70% of the length of said first member and extending from a respective end of said first member, and providing on said other member at least one slot which is shifted radially from said slots on said first member and extends from a respective end of said other member;
• and
• wherein a length of each slot extending from the left and right ends of the sleeve runs parallel to the single axis.