The white gallon pump dispensers are available in a 38/400 size. The white pump dispensers fit the 1 gallon natural HDPE round handle jugs, and the 1-gallon natural HDPE smooth square handle jugs. The white gallon pumps dispense 1 oz of product per stroke. These dispensing pumps are great for dispensing products such as lotions, soaps, and cleaning products. Be sure to test the 1 oz white gallon pumps with your product for proper compatibility.