I bought both metal and polyurethane (sp?) years ago from Robt Berthold Jr/Delaware Valley College/Doylestown PA 18901 (he makes them himself!) but in retrospect I could have done better if purchased from any of the following (ask 4 free cat): 1 Brushy Mt Bee Farm 610 Bethany Church Rd Moravian Falls NC 28654 usa 1-800-beeswax 2 Mann Lake Ltd County Rd 40 & 1st St Hackensack MN 56452 usa 3 Betterbee Inc RR4 Box 4070 Greenwich NY 12843 4 Glorybee Pob2744 Eugene OR 97402 - 800/465-7923 5 Lapp's Bee Supply 500 So Main St Reeseveille WI 53579 - 800/321-1960 Incidentally, you can see Berthold in operation in Coggshall/Morse's book, BEESWAX: Production, Harvesting, Processing & Products (Wicwas Press, Ithaca NY 14850, 1984, 192pp, soft). Bonne chance. Jack the B-man Ellicott City MD usa