Pine Car Performance & Conformity System Kit from Woodland Scenics. Portable, digital scale and conformity gauge keep you up to speed on your racer’s weight and dimensions. Instantly check car weight to within .01 of an ounce. Measure overall width and length, width between wheels, track clearance and locate the car’s center of gravity with the handy fulcrum point. Use the mathematical formulas and simple table to determine optimum placement for your car’s center of gravity (CoG). Adjust for optimum speed and stability. Kit Contents: Digital Scale, Double-sided Reference Ruler, CoG Formulas, CoG Table for 5 oz Cars, Two AAA Batteries.