Splice cassettes for optical cables and optical devices may include a tray base having a tray top surface. A tray center portion may be defined on the tray top surface inside a plurality of tray cable securing members arranged around a center-portion periphery of the tray center portion with a tray proximal zone and a tray distal zone. A device holder may be removably and hingedly attached to the tray base. An inner surface of the holder may have a holder proximal zone in which at least one device securing member may be disposed and configured to secure an optical device to the inner surface. When the device holder is closed and an optical device is secured in the at least one device securing member of the device holder, the holder distal zone may overlie the tray distal zone and the optical device may overlie the tray proximal zone.