The Valken Biodegradable Accelerate ProMatch Tracer 0.28g airsoft BBs are manufactured in Taiwan by one of the best known Airsoft BB manufacturers. These 6mm plastic BBs glow bright green when using a tracer unit or tracer magazines. They are precision grade quality, completely spherical, and polished to ensure that the BB is seamless and has no surface imperfections. These 6mm precision BBs give you greater accuracy and consistency, and they are packaged in a unique rectangular bottle with a screw-on cap making storage, transport, and loading simple and convenient. Accelerate BB bottles do not roll around like other round bottles, which can spill easily. We recommend our Valken Kilo Tracer Unit for use with Accelerate BBs