Jagwire 4mm Open Nylon End Caps Black, Bottle of 100

From Backcountry

Open end caps deliver low friction performance and are less expensive, but do little to protect the system from contaminates. Great for use on bikes with uncoated cables in areas with a lower chance of contamination from water or dirt, they are available in multiple sizes, materials and colors. Use open end caps when little protection from dirt is needed, in areas such as levers.