Product Name: Washer Type D/DIN 6319 D Model NO.: DIN 6319 Spring Washer Type: Heavy Combination Washer Structure: Conical Material: Steel Type: Spherical Trademark: BOESION Transport Package: Pallet Specification: M6-M64 Origin: China HS Code: 7318240000 Product Description concial seat washers are used for clamping on non-parallel surfaces.When utilizing DIN 6330 type B fixture nuts with spherical end, use either the type D or type G spherical dished washers. The type C spherical seat washer is not required.