Square Post Base 1-5/8" Unistrut B-Line Channel Strut Mount #4774 P2072ASQ EG | eBay
Morris Products 17454 Post Base Channel 4 Hole Square – for 1-5/8” Strut – Side Orientation, Galvanized Steel – 6” x 6” Base – Secures Strut Assembly to Floors, Surfaces, 1-Pack: Conduit Mounts: Amazon.com: Tools & Home Improvement
Strut Channel / C Channel / Channel Bracket System Base Plate, Unistrut Connecting Plate
6'X6' Single Square Post Base, Post Bracket for 1-5/8' Strut Channel, Hot DIP Galvanized - China Single Post Base, Post Bracket | Made-in-China.com
The Traffic Sign Store: Economy U-Channel Surface Mount Base
Post Ground Anchor | 42" U-Channel - Traffic Safety Products
4 Hole Post Base Channel, 6" Square for All 1-5/8" Strut Channel, Side – Automotive Authority
Phoenix Support Systems 3-1/2" Tall Strut Channel Post Base at Menards®
1 5/8 in x 3 1/4 in For Strut Channel Size, 9/16 in Hole Dia, Post Bases for Double Channel - 253T06|FS-5816SQ E/G - Grainger