Hello All, My name is Robb St. Cyr I am a database developer for Cyrious Software, we create a Shop Managment System/POS For the Sign industry, we are about to release our new dataset for channel letters and neon, however I am having an issue with the gas calculations and finding any info there, the main questions is how much gas is used, understanding that diffrent gasses may be used at diffrent pressures, so will very. I am interested in how you may be calculating it currently. Can I say That k-4 for example gets X per cubic feet of tube volume (Diameter * Length) / X ) = Y Liters). Does this make sence to you or is anyone using a different method. and if so were do you think I might be able to find the Value of X for the diffrent gases.(This wil be used for Costing Neon). Any help would be greatly appreciated.