Safety Eligibility Letter SS-21
Hardware Type:
Sign Supports, Mailboxes, and Delineator Posts
Code:
SS-21
Date:
Testing Criteria:
NCHRP 350
Manufacturer:
Minute Man Breakaway
Device Description:
MMB-1HD breakaway device with two 3 #/ft flanged channel "U" posts in both strong and weak soil.
View PDF:
ss21.pdf (170.52 KB)
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L.A. Staron, Chief
Federal-Aid and Design Division
Geometric and Roadside Design Acceptance Letter Number SS-21