Installation Kit For the 3D603, 3D604, XS 306, XS 307, XS 308, and 308, XS 308. Supplied with metal ring (position 1) and screws (position 2). The plastic ring (position 3) is part of the supplied tankrussak. Tank socket for: BMW F 650 GS / F 700 GS / F 800 GS (0