The Ruffneck™ Heater Sizing Calculation Tool program is a Java Applet and requires Java Platform support on your computer. If the Calculation Tool does not load and/or if you see a blank box or a blank box with a little red X in the corner instead of the Calculation Tool, you may not have the Java Platform installed on your system. To download the Java Platform, click here. Once you have installed the software, reboot your computer and try to load the Calculation Tool again. If it is still not working after installing Java, please contact CCI Thermal Technologies Inc. for further assistance.