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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
B-14 NCHRP 350 Smith-Midland Corp. Longitudinal Barriers and Bridge Rails J-hook connection for precast concrete median barriers.
SS-20 NCHRP 350 Franklin Steel Sign Supports, Mailboxes, and Delineator Posts 2 to 3 pound-per-foot flanged channel "U" posts.
LS-22 NCHRP 350 Akron Foundry Luminaire Supports Chart summarizing approval letters ls2, ls4, ls9, ls15, ls19
LS-21 NCHRP 350 Shakespeare Products Luminaire Supports Fiberglass poles ASW27 thru ASW35 and AHW27 thru AHW35 with Al shoe base
LS-20 NCHRP 350 Union Metal Luminaire Supports A2849 Al Transformer Base, 15" BC
LS-17 NCHRP 350 Akron Foundry Luminaire Supports CS-300 and CS-370 Al Transformer Bases (tests of Feralux bases)
LS-19 NCHRP 350 Akron Foundry Luminaire Supports TB-3-17, TB-5-9, TB-6-9 Transformer Bases, 11.5 to 15.5" BC
LS-18 NCHRP 350 Akron Foundry Luminaire Supports F-1300 and F-1302 Al Transformer Bases (tests of Pole Lite bases)
SS-19 NCHRP 350 Allied Tube and Conduit Sign Supports, Mailboxes, and Delineator Posts Square-Fit signpost systems.
LS-16 NCHRP 350 Valmont Industries Luminaire Supports Slip Base specifications