Image Storz without Screen Markets Fire Protection Product Options Part Number Female Thread Size Size Thread Female Thread Seal Material Color FDC400T 4" 4" 4" Storz x 4" FNPT FNPT Rubber Aluminium Black FDC400BS 4" 4" 4" Storz x 4" FBSP BSP Rubber Aluminium Black FDC500T 5" NPT FDC500BS 5" BSP