The EPS-55CS SD is an alternative needle (replacement needle) that performs as well as the OEM needles that are not the original manufacturer made for use with National record cartridges. This replacement needle is a "synthetic diamond needle" type. This is a generic model that plays a regular range of sound ranges, with a standard conical shape. General life is about 200 hours. The successor to the N.36-P55 EPS-55CS TR.GRN (4951586256359).