Uninsulated power transformers will have no (or only some) wildlife protection equipment installed.
Uninsulated power transformers have many dangerous components and if any one of these areas (circled below) are touched by wildlife they will be badly electrocuted. The voltage is high towards the top of the pole and gradually lowers towards the bottom, but all areas can, and usually are, fatal. This is an example of only one style of transformer – there are many different styles of transformers with different components, but all with have at least two of these six main components.
The insulation equipment is grey in color and made of silicone rubber. With a quick look, you will be able to instantly see if a transformer has been insulated by looking for these key wildlife protection equipment components: