Sorry to bump this but I verified which anchor we have, and thought I'd add to the virtual knowledge base.
It is a Rocna original 25kg and it fits perfectly own the rollers of our 37.
I bought it in Tasmania after dragging a 45lb CQR all over the place. The holding is terrible in many places there. We never dragged again.
John and Alison
1981 PSC 37
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