10 Pack of Square Piezo Tweeter (rear/flush mount) from Unbranded 85mm x 85mm, Rear Mount, Baffle Cutout 73mm diameter, originally manufactured by CTS (formerly Motorola)
Vintage Original Motorola Piezo Tweeter KSN1001A | #1824482947
4 Pair of 3.25" x 3.25" Piezo Tweeter Element DJ Speaker Car Audio Square Single Super Horn NTX-1004PZ - Best Connections
GRS PZ1005 3-1/4" Piezo Horn Tweeter Similar to KSN1005A