SurgiVet Ventilator Bellows. Additional bellows may be purchased separately for the SurgiVet® Ventilators. Bellows can be used with the MRI 2550 Ventilator and SAV 2500 Small Animal Ventilators. Includes bellows and base. Available in Paediatric 300ml or Foal 3 litre. Bellows only available on request, contact our office for details.