The original insulators on the Hustler vertical antennas become brittle over time and may break. This is a very close approximation of the original bottom / base insulator. I did not include the outer three screw holes as it's difficult to measure. Instead I simply held the insulator up to the antenna, used a marker to mark the correct locations, and drilled holes for these three. Other than that, it should pretty much be a drop-in replacement.
Designed from scratch in TinkerCAD, using pieces of the original broken insulator and a pair of calipers to take measurements. Printed in PETG at 50% infill.
The author hasn't provided the model origin yet.