Fit this cover over your electrical panel buttons for an effective way of preventing access to the button during essential maintenance.
The cover is extremely easy to install - first, a base plate must be fitted to the panel, using screws, bolts or super-strong adhesive backing. Then a circular section must be installed over the button, and can be opened and closed as needed. During maintenance the cover should be shut and secured in place with a lockout padlock (sold separately) and a tag to alert people around.
This lockout is also available in a larger size (55mm) rather than this size, which is 45mm.