Yes, they are old-school wired mics that look like the cheapest of off-brand earbuds (and the plastic oyster case looks like a Sony earbud case).
Mine are OKM Classic Rock Solo, $110 shipped from Soundman on Ebay in 2017. Looking at the site now that would seem to be the OKM Klassik II, the higher-SPL version (they all look alike). Soundman also sells on Ebay, but only a few things at a time.
http://www.soundman.de/en/products/Soundman sells its A3, a 6V battery module, to go with them, but I saw it got very mixed reviews. The mics will take up to 10V (per Soundman) so I am using my 9V CA-UBB. Doesn't get much more compact than Soundman-->CA-UBB-->PCM-M10.
They do go in your ears and despite the minimal size and the special foam covers, they are not quite acoustically transparent--vocals are a little harder to decipher during the performance. But on playback, the mix is right.
When I saw the Hooke in its Kickstarter days I thought it might be a good alternative to clip-on mics. If Sennheiser comes through with Android on its Ambeo binaurals, that might be the next step, unless Hooke has gotten its Bluetooth bugs worked out. No point in using the Hooke wired to a recorder when the Soundmans are so superb.