I have an 11/16ths Spike. Excellent razor. Referred to as a wedge, but really a quarter hollow and will take a fantistic edge. They come in white and green scales, plus there is a "Special Spike" that is dressed up a bit more.
Many of the eBay examples are beat-up, over honed 9/16th blades. You will have to sort through a lot of goats to find a larger size in better condition. I really think 11/16ths was as big as they came as I've never seen a 6/8ths Spike. There may be one out there, and someone may post that they own one, but if it exists it is rare. Really nice Spikes will cost $75 rather than the $20 most of the eBay ones bring.
I find the Case Red Imp 132 shaves about the same.
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