Volume #2 has 15 t-nut locations. It's overall size is comparable to a basket ball. It attaches using one bolt.
Volumes are awesome to break up mundane flat terrain or to ease up super steep walls. They bring a multi dimensional aspect to your wall.
Considering that this is one of the smallest volumes on the market and priced to hook our brothers up, you simply can't go wrong with it on your wall.
See above thumbnail image for measurements.
Note: The Volume does not include the holds to bolt on to it.