Stop buffer, component of the anti-vibration system. Models: MS 261 MS 261-VW MS 261 C-BE MS 261 C-Q MS 261 C-M MS 261 C-M VW MS 261 C-BM MS 261 C-MQ MS 271 MS 271 C-BE MS 291 MS 291 C-BEQ MS 291 C-BE MS 500i MS 500i-W