This dispensing gun is for use with Quiet Glue Pro 5-gallon pails and Green Glue Noiseproofing Compound 5-gallon pails. Easy Application: To use, simply insert the tip of the dispensing gun into the bucket and pull back on the handle to suction product into the dispenser. Then squeeze the trigger to apply product. This dispenser holds the same amount of product as 1 standard tube of noise proofing compound, so the same application rate of two dispenser-loads per 4x8 sheet of drywall applies. If you are using Quiet Glue or other noise proofing products in tubes, instead of pails, you need a standard 1-quart caulking gun, not this dispensing gun.