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FHWA Highway Safety Programs

Archived Hardware Eligibility Letters – NCHRP 350

These letters are archived and are posted for "historical and research purposes only" per the sunset dates in the AASHTO/FHWA Joint Implementation Agreement and exceptions to these dates as posted on the AASHTO Committee on Design website.

Letter Date Testing Manufacturer Hardware Type Device Description
SS-57A NCHRP 350 Marion Steel Company Sign Supports, Mailboxes, and Delineator Posts Redesigned Rib-Bak
SS-05A Marion Steel Company Sign Supports, Mailboxes, and Delineator Posts Redesigned Rib-Bak
SS-18A NCHRP 350 Marion Steel Company Sign Supports, Mailboxes, and Delineator Posts Redesigned Rib-Bak
SS-13D NCHRP 350 Marion Steel Company Sign Supports, Mailboxes, and Delineator Posts Redesigned Rib-Bak
SS-64 NCHRP 350 Marion Steel Sign Supports, Mailboxes, and Delineator Posts Metric "Rib-Bak 2" Posts
SS-56B NCHRP 350 Marion Steel Company Sign Supports, Mailboxes, and Delineator Posts Redesigned Rib-Bak
SS-63 NCHRP 350 S Square Tube Products Sign Supports, Mailboxes, and Delineator Posts Perforated square steel tube sign supports
B-37 NCHRP 350 Wyoming DOT Longitudinal Barriers and Bridge Rails DOT 2 Bridge Railings (Steel Post & Rail w/ Curb)
(TL-3 and TL-4)
CC-35 NCHRP 350 Energy Absorption Barrier Terminals and Crash Cushions QUADGUARD Crash Cushion - for unidirectional traffic @ TL-3
CC-34 NCHRP 350 Trinity/SYRO Barrier Terminals and Crash Cushions MPS 350 TMA @ TL-2