Blackmagic Design offers these Wing Nuts as spares or replacements to use with various accessories for your URSA Mini camera. The set consists of four wing nuts, each with a washer and spring. Blackmagic Design BMUMCA/SKWNUT Specs Packaging Info Package Weight 0.11 lb Box Dimensions (LxWxH) 1.85 x 0.8 x 0.5″