Most effective on existing
Spikes are most effective on existing perimeters that ideally exceed 1.8m in height. Their purpose is to prevent a hand-hold on a fence/wall that is already difficult to scale due to its height.
Spikes can also be installed in conjunction with electric fencing as an additional deterrent and to provide a physical barrier should the electric fence be out of order. Spikes can, in certain circumstances, be installed above gates.
Spikes are also commonly used to prevent access to trees and poles that may assist a potential intruder to scale a nearby fence.