A telecommunications assembly includes an adapter unit, a tray, and a telecommunications component. The adapter unit can be formed with a main body defining a first attachment feature disposed on a bottom side of the main body and a second attachment feature disposed on a top side of the main body. The tray can define a base wall and a side wall extending from the base wall, the tray defining a third attachment feature removably interconnected with the first attachment feature. The telecommunications component can define a fourth attachment feature removably interconnected with the second attachment feature such that the telecommunications component is attached to the tray by the adapter unit, the fourth attachment feature being incompatible for attachment with the third attachment feature.