I have an OEMMAX MCK-860 and this does look like one as well but I have never seen it with the RJ10 connector.
EDIT: Also looks like there is a din connector that comes out of the case which is interesting.
Thanksthe_ambyguous wrote: ↑08 Apr 2019, 12:10sold that same exact set about a year ago for $60. depending on how much shine there is/condition they may be worth more. or less.