Cups Fit for Netilat Yadayim

1. A cup of any material is fit for netilat yadayim as long as it can hold a reviyit of water.
2. If it has a hole in it or cracked such that it would let in water if the cup was placed on top of water then it is unfit for netilat yadayim even if the cup can still hold a reviyit below the hole or crack.
3. However, if the cup was made specifically so that there was a hole but with a support or something else it could hold a reviyit it is fit for netilat yadayim. For example, it is acceptable to wash from a canteen with a spigot that when opened water flows out of the hole and when closed can hold a reviyit of water.
4. If a kli is round or wobbly and can't sit without being supported or leaned against something so that it can't hold a reyivit without any support it is unfit for netilat yadayim.
5. It is unfit to wash one's hands with water that was contained in someone else's hands. According to Ashkenazim after the fact it is acceptable.
6. It is unfit to wash netilat yadayim from a faucet since that isn't considered poured with the force of a human being.
7. A paper or plastic cup is fit for netilat yadayim if nothing else is available. It is preferable to have in mind that one is going to use it again and not throw it out immediately.
8. A bottle with a thin opening can be used for netilat yadayim as long as the water is poured out constantly without interruption.