Keeping things simple (and lightweight), this dipole/doublet centre is great for portable operating or even for low-profile use at the home QTH. Strain-relief holes are provided and the direct feeder connection allows you to mount it high up a telescopic fishing-pole without the extra weight of connectors. These are precision laser-cut so for extra strength you could glue 2 together if you really wanted. Their bright-yellow colour makes them easy to find if dropped in long grass.
Pictures 3+4 show how to wire them up using coax or balanced feeder. Cable-ties can secure the feeder for a more robust fit.
Just add some aerial wires plus RG58/RG174 coax or balanced feeder for a complete fixed/portable HF aerial solution. If used as part of a Doublet, you will need to convert the balanced feeder to coax - best practice is to use a current balun and the shortest length of coax possible. A 1:1 Current Balun (aka: Choke) is preferred in most cases over the typically "QRP" 4:1 voltage balun found in many ATUs.
Something familiar on Youtube! Flattery is when you notice your product on a Youtube thumbnail. Thanks to Tim G5TM, this video shows the centre-piece in use on his End-Fed aerial.