Modular Ramps (MR) Ramp thresholds are often used to transition offset floor conditions. These shapes are designed to meet the requirements for accessibility. Barrier-Free Ramp ThresholdsThe modular ramp thresholds are an improvement over the 257/259 however, 257/259 will remain available for special requirements. Miter Returns For All Modular Ramp ThresholdsCast aluminum wings fit into each end of modular ramp threshold assembly, and are fastened to ramp mid-sections with self-tapping machine screws. Rubber Ramps and Components Threshold Assemblies - Components/VariablesUse a variable to accommodate offsets from 1/2" to 1-1/4". These meet the 1:8 maximum slope allowance (ADA) for existing buildings. Threshold Assemblies - Flush ApplicationsThese ramp assemblies consist of interlocking components, eliminating the need to weld joints. These assemblies can be configured to accommodate changes in floor conditions from 1/2" to 2 1/4". Threshold Assemblies Offset Applications (3-1/2" Top Plate)These ramp assemblies consist of interlocking components, eliminating the need to weld joints. These assemblies can be configured to accommodate changes in floor conditions from 1/2" to 2 1/4". Threshold Assemblies Offset Applications (7" Top Plate)These ramp assemblies consist of interlocking components, eliminating the need to weld joints. These assemblies can be configured to accommodate changes in floor conditions from 1/2" to 2 1/4".