Our double high industrial safety steel guardrail uses 42" high posts and accepts 2 rails per section. All posts have inserts on all 4 sideds to accept rails on all 4 sides of the post to provid maximum versatility. Heavy duty posts are 4.75" x 4.75" x 3/16" thick steel with 10" x 10" x 1/2" thick heavy duty base plates. Each baseplate has (4) 7/8" diameter holes to accept 3/4" x 4 - 1/4" long concrete wedge anchors. Rails are 12" high x 1/8" thick double ribbed steel. Powder coated safety yellow for maximum visibility. Impact rating: 12,000 lbs. at 4 mph crash test. 2' - 10' long rails available in 1' increments.