These blocks/risers/bases are clear transparent acrylic. They are all 1.00" thick. Please look at our other listings for thicker bases/risers. They all come with silicone bump-ons on the four corners of the bottom to protect the acrylic from getting scratched and to keep the base in place firmly. All of our bases come hand polished not by machine so all the corners are square and flat. Our bases can be found in homes under statues and art pieces and in museums all over the country showcasing whatever object is placed on them. We have been around since 1961 so purchase with confidence that you will receive a beautiful perfect piece. We do all our own work and we carry in stock acrylic from 1/16" thru 4.00" to service our customers properly. Call 800.200.4228 or go to our website at www.theplasticsmart.com Also go to our YouTube channel where we upload videos all the time and you can find videos of our products. https://www.youtube.com/channel/UC0ZIFYHOQ1bnf-B2Hg00mBA