SIPTENK 228PCS BRASS COMPRESSION SLEEVES FERRULES FOR 6 SIZES OD TUBE: 1/2" 18pcs, 3/8" 30pcs, 5/16" 30pcs, 1/4" 50pcs, 3/16" 50pcs, 1/8" 50pcs. EASY TO INSTALL: The brass ferrules sleeves, used with plastic and copper tubing, can connect lines for air, water, fuel, oil and inert gases, while inserts are mainly used to insert into hoses quickly and easily.
eBay