POSH is one of the famous aftermarket brand in Thailand. They have produced some of the best accessory for many bikes.
This one is an auto chain tensioner that can maintain a good tension for your roller chain. When you have good tension of the chain, it will last longer. Auto chain tensioner also eliminates chain vibration and chain sound that usually found in Yamaha and Modenas cub bikes.
This item is for sale at motomalaya.net/store