This is really a little gimmick to help electricians.
When pulling cables, large and small, you often use electrician tubes to help with the pull. To make it a little easier to push the tube through holes and over the cable trays I have made two different tips and two sizes 16 mm, 20 mm. One is slanted to make it easier to slipping over obstacles and a the other is tip to pass through holes, walls, walls, etc.
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