Not much to look at. The antenna sets that I bought ended up in M6 threaded inserts, so I bought M6 brass bolts and 2mm Nitinol wire. I had a machinist (because I don’t have the tools) put the appropriate holes into the bolts, then I heat the bolts and shove the wire in. Once that cools, some heat-shrink over the Nitinol, and some little green plastic caps I found on Amazon. I made six just in case, but they’ve all been on the car for months now and I see no issues at all.
The Nitinol wire isn’t cheap, and it’s hard to cut, but it won’t take a bend no matter what I might hit. Worst case I have to warm them up a bit to remove a small curve. VERY flexible. If you’ve seen HT whip antennas that get “droopy” in the cold, that’s nitinol.
The antenna kits I bought had telescopic antennas with a foldover at the bottom, which was pretty much a disaster waiting to happen, so I ditched those.
My option - no compromise.
I did not buy Kraken antennas. I made 5 pieces of J-pole antennas for 433 MHz and another 5 pieces of J-pole antennas for 145 MHz. A disk with a radius of 300 mm is attached to the roof of the car using five strong magnets. The disk is made of plywood, because the J-pole antenna does not require a ground plane. On this disk, the installation locations of antennas for frequencies from 1700 MHz to 300 MHz are marked. If you need to look for a transmitter with a frequency of less than 300 MHz, then five beams can be quickly attached to this disk. The beams are also made of plywood. In this case, the radius of the antenna is 750 mm. The beams also have markings for attaching antennas for different frequencies. And of course, I made five cables, each 4 meters long. The accuracy of the length of each cable was checked using an AD8302 phase detector.