The Grizzly and RuMble Grates are patented and trademarked products and have a patented methodology. Before the invention of the of the Grizzly and the RuMble Grate (or the subsequent various knock-off copies of the product existed), only gravel pads were used to control track out.  In late 2001, the Grizzly and the RuMble Grate were created and introduced in Arizona, Nevada and California on construction sites.  Since then it has spread across the country as the simplest and most economic way to minimize track out. Very quickly various "knock-offs" were being built to copy the rumbling effect of the Grizzly and the RuMble Grate in the form of rumble strips, steel plates and products under various names with actual limited performance as compared to the Grizzly and the RuMble Grate.  The Grizzly and the RuMble Grate has a collection space underneath which separates and collects the dust, dirt and rock falling off from the vehicle.  It uses no water or electricity but effectively collects the solid materials.  Patents numbers 6,981,818 and 6,881,006 and 7,059,799 were product patents focusing on the product itself.  Patent 7,775,739 was the methodology that the products introduced.  If you are a company attempting to copy this technology, you should be aware the method and product (regardless of the physical characteristics of your knock-off device) is Federally protected. 

Since that time there are "knock-off" products produced violating the Federal patent laws, which also do not perform effectively.  The infringers of this simple technology will eventually be addressed. Those organizations wishing to utilize the technology should understand that the Grizzly and RuMble Grate configuration was based on hundreds of attempts to get the exact spacing and elevation drop of the horizontal members to appropriately shake and vibrate vehicles; yet cause no physical damage to those vehicles driving over the Grizzly or RuMble Grate.  The Grizzly and RuMble Grate can be custom built for heavy trucks only or built for a combination of heavy trucks and light vehicles.  We know the proper dimensions to produce the desired effect based on the traffic exiting the property. The use and application drives the proper construction of the product.  A properly set-up and  performing Grizzly Rumble Grate will remove 80% of the material typically tracked out, depending on soil and moisture conditions.'

The Grizzly and RuMble Grate were designed to be installed permanently on landfills, power generation stations, mining operations, and petroleum processing plants. It was also designed to be used temporarily on construction sites for track out control and erosion control. The Grizzly and RuMble Grate can be set-up to be used and moved from one construction jobsite to the next.  Any contractor who has used a Grizzly or a RuMble Grate instead of a gravel pad have been impressed by the savings in road clean-up the Grizzly or RuMble Grate produces.  The savings on a typical construction site will pay for the capital cost of the Grizzly or the RuMble Grate, but it can used over and over and over again on multiple projects. The Grizzly and the RuMble Grate is built for longevity and strength, achieving an ASHTO HS-20-44 rating, easily handling vehicles and equipment far exceeding 85,000 lbs. for many, many years as seen in Erosion Control Magazine, Grading and Excavation Contractor and Site Prep.