ST Keystone module, SM (metal), black (similar to RAL 9005), - for mounting adapter KMK-MA Up rw/sw and other installation adapters, - slotted ceramic sleeve, - with dust protection caps, - in accordance with the following standard requirements:, - ISO 61754-2, - MM PC, Grade B or SM (PC/APC), Grade B, - service life > 1000 mating cycles