When the tip disintegrates, it melts and helps solidify the weld to the base material. Arc studs range from a #8 to 1 1â4  diameter. The lengths are variable from 3/8 to 60 (for deformed bars). Arc studs are typically loaded with an aluminum flux ball on the weld end which aids in the welding process.
Quoted from wiki: Inevitable discovery is a doctrine in United States criminal procedure that allows evidence of a defendant's guilt that would otherwise be considered inadmissible under the exclusionary rule to be admitted into evidence in a trial.
The theory of broad rights of discovery is that all parties will go to trial with as much knowledge as possible and that neither party should be able to keep secrets from the other (except for constitutional protection against self-incrimination).