Many streets are bracketed by bollards or Jersey barriers so as to keep out vehicles. Layered security often starts with fencing, bollards and mantraps. Examples are street lights, traffic signals, signs, bollards, telephone kiosks, CCTV and advertising displays. The deck will be reinforced around deck fittings such as the capstan, cleats, or bollards. The fence and some of the low stone bollards around the monument were heavily damaged. Permanent safety bollards were installed starting in July 2018. The pier includes a playground with historic bollards preserved from the pier's original industrial use. Pillar-shaped movable bollards fulfill a similar function. This is often done in practice by means of physical barriers (i.e. traffic bollards). Flexible bollards are bollards designed to bend when struck by vehicles. The new version, with protective concrete bollards, was unveiled April 27, 2018. Anti-ram bollards that fit architecturally with Pariser Platz were also agreed upon. It features painted bollards, mosaics and murals. The most expensive bollards can stop vehicles at speeds of about . Permanent bollards can be used for traffic-control or terrorist prevention purposes.