Hexatronic SRS10617/5 (Millennium part 523408) is a black rubber end sleeve protector for 24-way microduct bundles with an outer jacket diameter of 38 to 45 mm. Where a bundle is stripped back at a handhole or cabinet, the cut jacket edge is a stress point and an open path for water into the bundle interior. The sleeve caps that transition, supporting the individual microducts as they fan out and shielding them from abrasion against enclosure hardware. Part of the Hexatronic Duct Seal system for OSP applications and matched to bundle OD rather than duct count alone.