Tube Size:1/8" 3/16" 1/4" OD ,5/16" OD,3/8" OD,1/2" OD. Brass Compression Insert and Sleeves Ferrules With Good quality Strong and high standard brass Package including: 3/16" Brass Compression Insert 25pcs 3/16" Brass Compression Sleeves Ferrules 25pcs 1/8" Brass Compression Insert 25pcs 1/8" Brass Compression Sleeves Ferrules 25pcs 1/4" Brass Compression Insert 25pcs 1/4" Brass Compression Sleeves Ferrules 25pcs 5/16" Brass Compression Insert 20pcs 5/16" Brass Compression Sleeves Ferrules 20pcs 3/8" Brass Compression Insert 15pcs 3/8" Brass Compression Sleeves Ferrules 15pcs 1/2" Brass Compression Insert 5pcs 1/2" Brass Compression Sleeves Ferrules 5pcs 1 ★Suitable for the outer diameter of the pipe:1/8"3/16"1/4" 5/16" 3/8" 1/2",Used with plastic,copper, brass or aluminum tubing. ★Material: Brass.Corrosion resistance, ductility at high temperatures, and low magnetic permeability. ★Easy to Use: These fittings are easy to assemble requiring no soldering, flaring or deburring. Standard Compression Fittings are suitable for a wide variety of applications.It can keeps plastic tube from collapsing when tightened. And prevent leakage. ★Package Include:🔷25PCS 1/8" ,🔷25PCS 3/16",🔷25PCS 1/4" ,🔷20PCS 5/16",🔷15PCS 3/8" ,🔷5PCS 1/2" Sleeves Ferrules and Insert ,Total is 230PCS Compression Fittings Assortment kit . ★Application: Commonly used to connect lines for air,water,fuel,oil and inert gases in a quick and simple way.