UNSPSC 31161720: Stop nuts

UNSPSC 31161720 Stop nuts, a Commodity code, encompasses elastic stop nuts and Grade 8 fastening hardware in various sizes and specifications that state and local governments procure as consumable inventory for transit operations, water treatment infrastructure, and routine maintenance activities. Recent solicitations show state and local buyers purchasing 1/4-28 zinc-plated elastic stop nuts, 9/16"-18 Grade 8 nuts, M8 hex fasteners with suspension springs, and related industrial fastening components in bulk packages (typically 25 to 100 units per order). The transit authority is the dominant issuing body under this code, with the Dallas Area Rapid Transit Authority (DART) accounting for four of five recent opportunities in the source block, all soliciting fastening hardware and small mechanical components for fleet and facility maintenance. One atypical opportunity—the City of Lavonia, Georgia water treatment plant improvements project—was incorrectly coded to this Commodity code despite encompassing a major construction contract; that solicitation is unrelated to stop nuts and does not reflect genuine activity under the code.

DART-initiated activity dominates the recent procurement landscape, concentrated in Texas (Dallas County), with solicitations posted in January and February 2026 for routine consumable purchases featuring tight turnaround windows (typically five to seven days from posting to deadline). DART requires all bids to reflect FOB Destination shipping with freight included, emphasizes timely delivery as essential to performance, mandates registration and submission through the BONFIRE platform, and enforces Net 30 payment terms with invoices submitted in triplicate. Representative recent opportunities include DART's solicitation for 1/4-28 zinc elastic stop nuts in 100-unit packages (due February 5, 2026) and Grade 8 nuts 9/16"-18 in 25-unit boxes (due January 28, 2026). A secondary opportunity—Riverside County, California's RFB for Cla-Val miscellaneous inventory parts (due February 13, 2026)—suggests occasional county-level procurement of specialized industrial components, though the parts specification diverges from the nominal stop-nut scope. No set-asides, disadvantaged-enterprise requirements, or incumbent vendors are identified in the available documentation; these procurements appear open to all qualified suppliers meeting standard compliance certifications.