4' 8" To 8' 4", 15 Gauge Adjustable Jack Post, Max Ext Load 9,100 LBS, Min Ext Load 18,000 LBS, Additional Support For Crawl Spaces, Attic, Staircase Or Decks, Adjusts With 3/4" Wrench, O.D. Gauge & Tube Dim 2-1/4" x 15 Gauge x 49", Screw Size 1" x 7",...