About this 3D model

带膨胀的球头支架，适用15mm的孔，如果尺寸不合适，请自行修改。 需要另外购买m8*65的螺丝，m8的锥形螺母。 Ball head bracket with expansion, suitable for 15mm holes. If the size is not suitable, please modify it yourself. Additional m8 * 65 screws and m8 tapered nuts need to be purchased.