[Material]: The screw of ring insulator is made of metal durable can be used as an essential electric fence accessories.[GreatInsulation]: The cover of fence ring insulators are made of black plastic which have great insulation property, sturdy, resistant to sun exposure and rain, very durable.[UniqueDesign]: The slot design can fix wire firmly and reduce the abrasion to lengthen the service life of wire and the ring design enables the wire to be inserted with one easy twist.The angled slot can hold electrified wire without energy loss, suitable for low impedance and standard load fence controllers.[Function]:To prevent electrical shorts between the electrified wire and the fence posts,keep the space between wires and post.[Easy to install]: screws easily into timber fence, no special tools or technical know-how neededColour: blackMaterial: plastic, metalSize: total length 82mm (see the picture for details)Package Contents:25 x Screw In Ring InsulatorsOnly the above package content, other products are not included.Note:Light and different displays may cause the color of the item in the picture a little different from the real thing.The measurement allowed error is +/- 1-3cm.