Flues Model Ithaca gun, built on three-piece lock mechanism invented and patented by Emil Flues. Introduced in 1908, remained in production through 1926 when it was replaced by Ithaca New Double. Offered in 10-, 12-, 16-, 20- and 28-gauge. Enjoyed longest production life of any Ithaca double gun. Several grades offered beginning with Field Grade and ending with Sousa Special. Flues Model had same bolting system as used on Minier Model. Any grade could have been ordered, with automatic ejectors at an extra cost. Single-selective trigger made by Infallible Trigger Company, offered after 1914 and was first single trigger offered from this company. NOTE: Add $200 for factory-ordered single trigger; $200 for automatic ejectors on grades lower than Grade 4. Small gauges command a price premium. 20-gauge gun may command up to 50 percent price premium; 28-gauge Field Grade, perhaps as much as 200 percent. Serial number range for Flues approximately 175000 to 399000. Expert appraisals are recommended on higher-grade, small-gauge models, as they are seldom encountered.