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properties /identity

property token a chosen word

filter form

How a filter is built and mounted — a sealed spin-on canister, a bare cartridge element, a framed panel, a cylindrical round element, a cone, an in-line body, an in-tank sock. One duty is served in several forms and they are never interchangeable: Toyota sells engine-oil filtration as the 90915 spin-on AND as the 04152-31090 element kit. Concern identity, so not axis-eligible — a spin-on and a cartridge are two products, not two cells of one buy box. Distinct from `shape` (the planar geometry a panel also states) and from the spine's length/width/height, which give the panel its size.

Filter form is answered with one word chosen from the filter forms list — the same word shared across every product that uses it.

It belongs to identity — who and what it is.

asked by the kinds that answer it

2 kinds answer it, each for a single value. The same question can be reused by unrelated kinds — one meaning, many homes.

answered with
token — a token — a word chosen from a fixed vocabulary, shared and filterable across products.
value domain
Filter forms — the vocabulary its answers are drawn from.
concern
Identity — the facet of a product it belongs to.

asked by kinds that answer it

The same question can be reused by unrelated kinds — one meaning, many homes.

kindhow many
filter one