1'7-3' 15GA Jack Post

1' 7" To 3', 15 Gauge Adjustable Jack Post, Max Ext Load 16,000 LBS, Min Ext Load 18,000 LB, 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 17", Screw Size 1" x 7", -5 Thread Support, Collar Size 2-1/4" x 1/2", Support Pins 1/2" x 3", 13 Gauge Plate Size 4" x 5", Corrosion Resistant Inside & Out, Double Carriage Bolt & Nut, Zinc Coated, For Added Safety, Heavy Plates Suited For Wood & Steel, Deep Dish Self-Centering Plates.