The DPA Microphones’ 3521 compact cardioid stereo kit provides a professional piano miking solution.
The 3521 is a complete stereo kit with two matched 4021 compact cardioid microphones designed especially for mounting directly inside a piano. The complete 3521 kit includes the combination XY/ORTF holder, two gooseneck mounts and two magnet bases for mounting on metal surfaces.
Comes fully boxed all as pictured
Here's a link to the Sound On Sound review >>>DPA MICS