If any of you are restoring a Guild amp, a pair of CTS 12" speakers on eBay Except for the red Guild label, these are the same speakers originally used in the T1 12s and T1 RVTs. I believe these are ceramic magnets; normally 3" or so square, 1/2 inch thick and the bell covers are understood to be plastic. Cones look decent but the condition of the voice coil governs; seller doesn't say they've been recently tested nor does he provide resistance readings across the coil. Mighta been 8 ohms when manufactured but ... CJ