The specs on the ECM-DS70P were something like:
100 - 15,000
sensitivity -38dbV+-3.5db
Noise level 34db SPL
Max input level 110db SPL (THD 1%@1kHz)
Uni plug in power
There may be hundreds of thousands of Bogus, Chinese , near exact looking fakes of these ECM-DS70P out there. One youtube member had a detailed video on how to compare the two and spot the obvious fakes, and he I don't think could be certain of all of them. The wire mesh grill sticks out further and is less rounded or more rounded? on legit one, possibly. All have markings and such that appear "real". Those $4 Hong Kong evil bay versions are 99.9999% to be imposters. Has anyone dissected both and tested/identified component quality differences. The housings are rather neat. One could seemingly easily just gut and re-construct with WM-55 panny's -youknees for couple bucks parts from digi-key.