I have a lot of extra snap rings from parts engines but I have never had a snap ring go zinging off into the void. However those itty bitty beveled valve keepers on the YS engines are another story. I had a clear plastic box with arm holes cut in it just for doing valve jobs. Then I found some really big baggies that are easier to use. The hardest thing to locate was a little chrome check ball from a Walbro carb. I always clean my shop and floor when doing this type of work but even then it's a head on the floor looking for these parts. The second the part takes off I freeze and listen.