Listing Detail Tabs
Olive is brass. Insert is stainless steel (slightly ferromagnetic). It's a good idea to replace Olives and Inserts whenever you connect/disconnect brake hoses.
The olives are symmetrical, and intended for 'standard' 5mm bike hydraulic hose. The inserts/barbs have an outer diameter of ~2.3-2.5mm; intended for use in hose with that internal diameter. Note that some newer Shimano brakes have hoses with narrower internal diameters of ~2.1mm (BH90 I believe).
Only work on your brakes if you know exactly what you are doing. If you install these incorrectly, or otherwise mess with your brakes and the fail on you, you could be seriously injured or killed.
That said, to install these cut the brake hose to appropriate length using hose cutters. Ensure the end is cut cleanly and square/flush. Clean all surfaces using appropriate cleaner, such as isopropyl alcohol. Allow to dry. Slide the compression nut (not included) onto the end of the hose. Then slide the compression olive onto the hose. Insert barb into the end of the hose. Use an appropriate tool (there is an intended/special tool for this task). If installed using another method, these or other parts could be damaged. Ensure that the insert is pressed in until it seats against the cut end of hose. Align the compression olive to slightly behind the end of the hose (as far as it will go with gentle hand force) Install the hose end into your caliper or lever. Tighten the compression nut according to the caliper manufacturer's instructions. Bleed the brake system according to the manufacturer's instructions.
Additional instructions (including videos) are available online.
Note that as these are not branded components, using them may void warranties on other parts.
Auction/price is for one set (i.e. one hose end) only. I'm happy to combine multiples into one envelope though. Normal CGA terms/warranty. These are a consumable item not intended for re-use.