NONIN WristOX 3150 Medium Soft Sensor Exercise Physical Therapy Matrixed Audio Tone and A B 01804 Matrixed Audio Tone and A B Ratio for Dual Channel Systems * The lightweight heavy duty aluminum means you don't have to worry about maintenance and ensures the Gateway Solid Surface Portable Ramp can be used in even the harshest of weather conditions * The lightweight heavy duty aluminum is more durable than wood allowing you to repeatedly use the ramp every day without worrying about deterioration * The one piece design of the Gateway Solid Surface Portable Ramp means no assembly is required * All you have to do is set it in place and it's ready for use * Slip resistant surface * Designed with a permanent extruded slip resistant surface the Gateway Solid Surface Portable Ramp makes sure that wheels don't lose traction removing the worry of wheels slipping on the ramp * Useable size: 4'x36 x3 For spot checks or continuous monitoring Nonin * Quick and easy spot check application