Attaches any 4x4 FiberRunner® Fitting or Channel to the 2x2 Fiber-Duct™ Channel, S2X2YL6 or E2X2YL6 or 2x2 FiberRunner® Channel, HS2X2YL6 or H2X2YL6. Note: Attachment to 2x2 FiberRunner® Channel requires a QuikLock™ Coupler FBC2X2YL. Includes solid cover.