Flap barrier turnstiles come in different shapes and sizes. Rectangular, square, and wedge-shaped flaps are common flap barrier shapes. These flap barriers can be waist high or full height, depending on the level of security necessary. Optical turnstile flaps can move by either swinging or retracting to open a lane. Movement, shape, and barrier height are all variations that help tailor flap barrier turnstiles to specific project needs.