Titanium ISO Standard Flat Washer 21 x 37 x 3.0 (M20 Use) Pure titanium (2 types) TP340 series Titanium is a metal that is extremely difficult to generate metal allergies as it is proven to be used in implant treatments and stabilizing fractures, etc. (*1) It is basically non-magnetic (*2) so it is used for measuring instruments. *1... This product is just for industrial use. Do not use for medical purposes. *2... Pure titanium alone is completely non-magnetic, but it may be possible to detect very slight magnetic properties on products due to the effects of additives and fine dust residues on the surface during processing.