# Scope
"Craft Fasteners, Closures & Hardware" (supplies > crafts > fasteners): sew/craft closures and small hardware — buttons, snap fasteners, zippers, hook-and-loop, hooks-and-eyes, grommets/eyelets, rivets, and strap hardware (buckles, D-rings, cord locks, clasps). Excludes magnets/magnetic snaps (sibling leaf `magnet-fasteners`), office/paper fasteners (sibling leaf `office-paper-fasteners`), and general sewing tools (sibling leaf `sewing-tools`).

## Seed
1. Equivalent of treadwear_grade: zipper gauge (#3/#5/#8...) is stamped on nearly every zipper pull, but the mm tooth width behind a given gauge number drifts slightly by maker, so it matches a replacement slider reliably within one brand and loosely across brands.
2. Perfumer-persona notices durability curve first: hook-and-loop's grip fades with wash/use cycles (hooks go bald) while a sewn snap, rivet or shank button doesn't degrade with cycling — "lasts" vs "fades" splits the category more than any spec sheet row does.

## Sources
- [wikipedia_zipper] en.wikipedia.org/wiki/Zipper — gauge numbers #3/#5/#7/#8/#10 — fetched excerpt: "common gauge sizes are #3, #5, #7, #8 and #10, the bigger the number, the wider the teeth/chain width is"
- [wikipedia_zipper] same — coil/plastic/metal tooth types and closed/separating/two-way/invisible mechanisms — fetched excerpt confirms all four mechanism types and three tooth materials
- [wikipedia_button] en.wikipedia.org/wiki/Button — ligne sizing and 2-hole/shank attachment — fetched excerpt: "16 lignes (10.16 mm... men's shirts) and 32 lignes (20.32 mm... suit jackets)"
- [wikipedia_line_unit] en.wikipedia.org/wiki/Line_(unit) — ligne = 0.635mm, corroborates button math — fetched excerpt: "one-fortieth of the US-customary inch (0.635 mm)"
- [wikipedia_snap_fastener] en.wikipedia.org/wiki/Snap_fastener — 4-part rivet-set construction (eyelet/socket/cap/stud) — fetched excerpt confirms part names
- [prym_snaps] prym.com/en/buttons-fasteners/press-fasteners — brand taxonomy splits sew-on snap fasteners vs non-sew press fasteners vs turn-clasps vs magnetic snaps — fetched link structure
- [prym_product] prym.com/en/metal-snap-button-88bf2... — sew-on snap diameter examples 23mm and 28mm — fetched excerpt: "Diameter (mm): 23" / "Diameter (mm): 28"
- [wikipedia_grommet] en.wikipedia.org/wiki/Grommet — small grommet = eyelet; use buckets (shoe/sail lacing vs tarp/sail vs curtain/craft) — fetched excerpt
- [wikipedia_rivet] en.wikipedia.org/wiki/Rivet — double-cap vs single-cap vs cutlery rivets; solid vs semi-tubular — fetched excerpt: "Double cap rivets have aesthetic caps on both sides. Single cap rivets have caps on just one side"
- [wikipedia_hook_and_eye] en.wikipedia.org/wiki/Hook_and_eye — individual vs ready-to-cut tape; stainless/nylon-coated/brass — fetched excerpt
- [wikipedia_hook_and_loop] en.wikipedia.org/wiki/Hook-and-loop_fastener — nylon hook/loop vs mushroom-stem (Dual Lock) heavy duty, PSA adhesive — fetched excerpt
- [wikipedia_webbing] en.wikipedia.org/wiki/Webbing — webbing breaking strengths "in excess of 10,000 pounds-force"; sized by width — fetched excerpt
- [itw_nexus] na.itwnexus.com — strap-hardware product families incl. Hooks & Retainers (Glovehook/Snaphook) and Locking Buckle (Key Locking/Center Release) — fetched excerpt
- [wikipedia_nickel_allergy] en.wikipedia.org/wiki/Nickel_allergy — EU nickel-release directive since 2004, metal buttons/zippers named as sources — fetched excerpt
- [wikipedia_cpsia] en.wikipedia.org/wiki/Consumer_Product_Safety_Improvement_Act — small-parts rule effective 2008/2009 — fetched excerpt (the page's separate "zippers or buttons" sentence is lead-testing, not this rule)
- [cornell_cfr_1501] law.cornell.edu/cfr/text/16/1501.1 — 16 CFR 1501 is the children's choking/small-parts test — fetched excerpt: "PART 1501—METHOD FOR IDENTIFYING TOYS AND OTHER ARTICLES INTENDED FOR USE BY CHILDREN UNDER 3 YEARS OF AGE WHICH PRESENT CHOKING, ASPIRATION, OR INGESTION HAZARDS BECAUSE OF SMALL PARTS"
- [wikipedia_nickel_directive] en.wikipedia.org/wiki/Nickel_Directive — names EN 1811 as the EU's prescribed nickel-release test method — fetched excerpt: "the prescribed test method for quantifying nickel release from products EN 1811"
- [wikipedia_carabiner] en.wikipedia.org/wiki/Carabiner — swivel-jointed snap hook with load-bearing latch, historical strap/luggage form — fetched excerpt

## Branches
- closure_type: the sentence "it decides which spec actually matters" (template's own framing, reapplied) — each value's spec sheet is disjoint per Wikipedia pages above (ligne for buttons, gauge for zippers, eyelet/socket/cap/stud for snaps).
- hardware_subtype (only when closure_type=structural_hardware): grommet/rivet/strap-hardware spec sheets are disjoint per wikipedia_grommet, wikipedia_rivet, itw_nexus.
- end_use: no then_ask branch — nickel-release (wikipedia_nickel_allergy) and CPSIA small-parts (wikipedia_cpsia) only change which judgement applies, not which facet is asked.

## Noise
- Zipper pull/slider style (fixed vs auto-lock vs decorative pull) — on some listings but not comparable across tooth-material rows on either source checked; left as a sub-detail of zipper_mechanism rather than its own facet.
- Snap setting-tool type (hand pliers vs press machine) — a workshop-equipment fact, not a property of the fastener itself; not on brand spec sheets as a product attribute.
- Rivet/grommet exact numeric diameter series — brand pages were rate-limited (429) before a second independent numeric source was reached; used Wikipedia's use-case buckets (lacing/tarp/curtain) instead of inventing a number range.
- Magnetic snaps — real press-fastener-adjacent product, but owned by sibling leaf `magnet-fasteners`; excluded per scope.
- Snap/button colour-finish and decorative shape (round/heart/star, from the Prym spec sheet) — cosmetic variants, not a spec a buyer must match; no facet.

## Corrections (2026-10-26)
- closure_type: rewrote all 6 branches' `makes_irrelevant` to list every sibling family's full facet set, not one representative facet each.
- strap_hardware_gate_type: added `swivel_snap_hook` and `locking_buckle` values (itw_nexus's Hooks & Retainers and Locking Buckle families had no value); explained all 8 values in why_experts_care.
- judgements: cited EN 1811 (nickel release, via wikipedia_nickel_directive) and 16 CFR 1501 (choking/small-parts, via cornell_cfr_1501); corrected the CPSIA note so it no longer leans on the "zippers or buttons" sentence, which is a separate lead-testing passage.
- snap_fastener_mechanism, rivet_style: explained `turn_clasp` and `semi_tubular`, which were in `values` but undefined in facet text.
- zipper_gauge: reworded backfill_note to flag the garment-tier mapping as this register's own inference, not a cited spec.
- grommet_size_class: relabeled `source` from `listing` to `derived`, matching the title-keyword-inference method already used for `closure_type`/`end_use`.
- Rejected: Part C's `hardware_subtype` legs needed no fix (checker found them complete). Part B's `end_use` split needed no fix (checker found it clean).