The British brought them to Sri Lanka in the 19th century as tea and rubber plantation workers, and they remain concentrated in the "tea country" of south-central Sri Lanka.
It exists in various versions, with individual or central focuser, with thick rubber armor or just a rubber skin, with - and without military reticle.
它有很多版本，包括双调和中调、薄橡胶铠装或者只是一层橡胶皮、有无分划。
3
The central area in front of the terminal building in the new Kunming Airport USES isolation system with large rubber isolation bearing which has been installed successfully.