Recommend you slice with concentric infill pattern at 100%. Cordage holes are 3mm and are meant for 1.8mm UHMWPE line.

If it won't fit on or over the hex fitting at the bottom of the antenna you may need to scale the print up slightly(102% worked for me), or put the antenna in your freezer for awhile. It was designed for a tight fit.

Fits chameleon antenna's military whip antenna so you can add guylines in windy weather. (MPAS 2.0)

Also fits this chinese antenna that is mysteriously exactly the same and half the price:

https://www.amazon.com/Manpack-Collapsible-Element-Antenna-Length/dp/B07DWN64CN