Line Set 9000 BTU Mini Split Air Conditioner (1/4&rdquo; X 3/8") - All Copper (16 Ft) with Insulation - Flared Fittings/Quick Connect Standard Size 1/4" x 3/8" - Commonly used for 9,000 BTU Mini-Split A/Cs 16 Feet High Quality Copper Line with Insulation Easy Connect - Flare Copper Nut Fittings