Some oak-slat trunks were made with alternating colors on the vertical slats. The radiator grille has metallic grey vertical slats. Wings fitted with slats and split flaps. The wing included leading edge slats and double slotted flaps over its full length. A Venetian blind has horizontal slats, one above another. Windows often appear as mere slits with narrow timber jalousies (often with adjustable slats). Hydraulic pumps for flaps, slats, speed brakes and other control surfaces are also powered electrically. Samples of moss were installed in the cracks between wood slats. The design featured four leading edge slats that deployed automatically, and large trailing edge flaps. The leading-edge slats and trailing-edge flaps were adjusted. These wings often use aerodynamic devices like flaps, slots, slats, and vortex generators. It is important to lock the automatic slats (leading edge flaps) during aerobatic manoeuvres. Transformations show a scene made up of vertical slats. These were similar in design to retractable slats, but were fixed and non-retractable. The tracks were by redwood slats.