It's a great, classic harness. The leather is the thickest I've seen on a harness, and decent quality for what I paid (under 50). The construction is solid and I know that it will last a long looong time.

Aside from sturdiness, what I really love is the adjustability. I use the D-ring version (I've seen others available with buckles) so I can slide them exactly where they need to be. The straps connect directly to the rubber O-ring in the front with snaps (more on that in a bit) so I can easily switch it out for a different size. There is a nice thick piece of leather behind the O-ring, and that can also be removed if you so desire. I love that the straps connect directly to the O-ring instead of the piece in front- it provides major control and stability, and it illiminates the possibility that one of the straps will tear from the piece in front and ruin the harness. It also means that the only limiting factor on the cock is the size of the O-ring- doesn't matter if it has balls or not, or is shaped like cthulhu... if it can fit in an O-ring, it will work with the Terra Firma.

My only gripe- the snaps connecting to the O-ring are a double edged sword. While they do allow me to switch it out easily, they also can come unsnapped at inopportune times. It took me a while to find the balance of fitting the harness tight enough but not so tight that one of the snaps would come undone. It's only happened twice but it was annoying to stop in the middle of things to snap it back in. It's not a fatal flaw, but if I were to re-design this harness I would try to figure out something that is harder to trigger accidently.

The vibrating corset harness from Eden

SpareParts Theo

Anything by spare parts.