FIBER OPTIC ADAPTER ST adapter has a metal housing an d either a precision zirconia or a rugged phosphor bronze sleeve.Zirconiasleeve enables stable connection and thus enhances performance,and is ideal for single mode applications.Phosphor bronze sleeve provides durability,and is ideal for multimode applications.We Manufacture fiber optic ST adapters,including the single mode and multimode types.These ST fiber adapters are simplex style and duplex style,most are with zirconia sleeves,optional bronze sleeve adaptors are available for multimode.