Pinewood Pro Tungsten Sphere Weights for Derby Cars | 33 Piece Set | 4.5 mm in Diameter | Incrementally Adjust Weight | Great for fine Tuning | Non-Toxic, Child Safe

These were an excellent way to add small weight to the car. Just drill bee-bee sized holes in the bottom of your car and you can glue these in to help get you near the 5 ounce limit.

My order had 31 tungsten spheres 1/8 inch in diameter. They weighed 0.95 oz.If you build a compartment into your car that can be opened these weights are perfect for making the final adjustment of the weight of the car right before the race. Last year I had to drill a great deal of wood out in order to reach the weight for the race although an analytical balance had shown the car to weigh 5.00 oz when we built it. This year I just opened the compartment with a screw driver, removed a sphere, and the car was exactly the right weight.

Pricey little boogers but do the trick. We used these to top off exactly at weight and ran quite well. We drilled vertical channels in a strategic location and capped so that we could easily reuse each year. With cost it would be foolish not to. Four of five stars simply due to that cost. Effectiveness would be five, just marginal in terms of value.

If you need to add a LITTLE bit of weight to the pinewood derby cars... this is great, but you might want to look into getting larger sizes if you need to add lots of weight. We ended up getting some fishing weights and drilling into the bottom of the car and adding quite a bit of weight... this was perfect to use when we weighed in at the derby (the scale said we needed to add just a little bit more... so we added this with some of the tungsten puddy, which was another great product to have on hand there).

Nice consistent weights for trimming the car. We eventually didn't use them on our vehicles but others did with the tungsten putty.

Tungsten is almost three times denser than steel and harder, as well. It is what they make armor piercing bullets from. I tried these with my bb gun, and it definitely increases penetration through cardboard. They seem pretty accurate, too.

These are tiny, and they feel denser than regular ball-bearings. They are good on race day, since every scale is just a bit different. These weights made it quick and easy to fine-tune my son's car and get it to exactly 5.00 ounces. If you need more weight, we used Pinewood Derby Weights - Tungsten 3oz.Considering that I could re-use these weights in following years, the price seems fair to me.

These help a lot to fine tune your car. Need the larger weights to get in the range and then load with the spheres. Little bit of putty to fine tune.