Definition
Put wall
Also called support strike
The put wall is the strike below the current price carrying the largest modeled dealer gamma from put open interest.
In more detail
It is the mirror of the call wall. Concentrated put open interest at a strike gives dealers a large hedging obligation around that price, and the resulting flows can slow a decline into it.
Like the call wall, it describes where hedging pressure sits rather than a level price cannot pass.
How Hermes measures it
Hermes publishes the put wall on every ticker page that has enough chain data to compute one, and omits it when the chain is too thin to support the figure.
Read this on a live chart.
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