Check the listing for details. Four Seamless Baluster Molds For Concrete Production. Condition: Used, Made in United States. Listed at 2385.00 USD. Wood and urethane rubber molds for the production of concrete balusters. One piece rubber with one cut gives a near seamless appearance. Dimensions, top 4 7/8”x 4 7/8”, bottom 5 1/16”x 5 1/16”, overall length 20 1/2”- 20 1/8”.