Make your pine cars zoom down a hill ramp by meeting your weight needs using the round PineCar® weights. These PineCar speed accessories help increase the weight of your derby cars, thereby making them faster. To use, drill a 0.375-inch hole in the vehicle and insert the desired weight into it to meet your weight requirements. The hole can be filled with body putty and sand before painting. Each derby car weight in this pack weighs approximately 1 ounce.