The Tectonic holders come with a multi friction compound set up, but single or dual compounds can also be configured. tectonic replacement inserts are only designed to fit into Kool Stop tectonic holders. Features: Water Grooves Integrated Pad-Lock™ Hardware Interchangeable Compounds Rim Friendly Brake pad holders not included! Pad Compounds: Black - Standard compound which is great for all weather conditions, but designed for dry condition riding. Salmon - Famous Salmon compound is one of Kool Stop's most aggressive compounds. Designed for extreme all-weather conditions especially in the wet, but still superb in the dry. Dual Compound - A fusion of Kool Stop's two finest compounds, black and salmon. Provides superb braking in all weather conditions. This combination produces a more controlled smooth stop. Ceramic (Green) - This Z-Chromium compound was designed for rims with a ceramic coated braking surface, and is great in all weather conditions. Made in the U.S.A