Two for sale, both working fine when removed:

80mm 1984 5Stv5S (fast response, needs 0.9 liter flask) 10 knots $200
57mm 1992 5StvM (normal response, needs 0.45 liter flask) 10 knots $200

Shipping free in the US, I can also throw in a free flask with each,
though I'm not 100% certain of the sizes...

Marc
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