This is Dave Powell’s latest Spirit Slates which is essentially a larger and slightly better quality version of the old CW effect the Slates of Solomon which in turn were based upon Milson’s (yes before Milson-Worth) Satyr’s Slate c. 1971.
This set of spirit slates are really beautiful and work without any flap or outside gimmick. They are ingeniously designed with the mechanism actually inside the slate. However, for most situations I prefer the slightly smaller CW Slates of Solomon.
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