I have several Shimano mountain bike and road bike pedals. As I love my long out of production PD-M747 I decided to buy some replacement kits. But it also means that the pedals I buy are heavily worn. So I learned how to disassemble and reassemble these pedals. And 100 bearings are enough to make 2 sets of pedals. Those bearings, some lube and cleaner and now I have 2 sets of spares for my bikes. They've gotten a few hundred miles so far and I expect they'll have many more miles to go with no problems.