It is very similar to the one shown in the webpage referenced above. It is a good mirror and I use this telescope for planetary observing, because it is such a good mirror and shows little distortion at high power. I also built a squating dog equatorial scope out of Berry's book and have it out on loan to Mac in Leander, Texas at this time. Some of the money saving alternatives we have come up with over the years includes using pieces of gutter strap and threaded rod to make our own secondary holders. It works great.
Secondary adjustment is done by just bending the strap until it lines up optically.
This seems to work quite adequately and not be too much of an obstruction. We have had few complaints from new telescope owners. This is an easy telescope to build if you can come up with the right materials. It is the shipping container for Carlon Multigard Flexible Bends and is usually thrown away. Beats waiting 100,000 years for it to break down in a landfill somewhere.