Do you mean for scuba diving?
Please give us some context with your query, that makes it easier to help you. And since this is a language forum, please pay attention to spelling, punctuation, grammar (benefitting those still learning).

Meinst Du eine Kopfhaube für einen Taucheranzug?
Bitte gib bei Anfragen immer Kontext/Beispielsatz an, dann kann man Dir besser helfen. Bitte achte auf korrekte Rechtschreibung,Interpunktion und Grammatik (hilft denen, die die Sprache erst lernen).

and before some smartarse points it out, yes, there should be a space before "Interpunktion".

This is headgear covering head and neck with a hole for the face. Worn by school kids and e.g. by racing drivers under their helmets.

What Cat means is a "Sturmhaube" in German. But I am looking for "Kopfhaube" as well. Think of people working in the food industry or at a bakery. They have to wear this on their head so their hair doesn't fall into the food or production chain.

@ chrispy
There's sooooo many varieties, you'd have to know the shape
try giggling for : skull cap, mob cap, snood cap, trilby, peaked hat, tallboy hat, forage hat
or: headwear catering industry

Hey laalaa,
Cheers. It was the mob cap I head in mind. So I guess your the specialist on caps & hats ;-)

Thanks a lot!
chrispy

@ Chrispy: Just talking through my hat :)