Greifsträhne

German to English Tech/Engineering Cosmetics, Beauty Hair analysis

These are one sort of hair specimen in a list - the other sort are "Kämmkrafttressen". I am translating the latter as "combing force tresses" i.e. samples of long hair to test combing properties. I'm not at all sure about "Greifsträhne" though, and would appreciate your suggestions. TIA, David.