#$%^&*AU2017204064A120181129.pdf#####ABSTRACT A variable height chair for positioning an accessory within a horizontal concrete forms, comprising a base portion having a vertically-oriented, internally-threaded socket, and an externally-threaded accessory that mates with the internally-threaded socket for screwlike travel within the socket. The internally-threaded socket includes at least one vertically-oriented internal detent, and the externally-threaded accessory includes at least one longitudinally-interrupted thread section so that upon rotational movement of the accessory within the socket the internal detent cyclically engages the interrupted thread section and positions the accessory at one of a plurality of regularly spaced-apart vertical positions with respect to the base portion.11/6 100 160 f180 140 110 122 127 120 120a12 129-10 126 128 FIG. 1
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