ThermoFlo Trach CRV Filter, 6241 - Box of 30. Brand: ThermoFlo. Manufacturer Name: Arc Medical. Manufacturer Number: 6241. Application: Trach CRV Filter. SOLD BY: Box of 30. With O2 port26 mg H2O/L Air Humidity VT 500 mLAt 0.7 cm H2O at 30 LPM Resistance12 mL dead spaceThe CRV may be used for suctioning without removing the device, and features an optional integrated O2 adapter for supplemental O2 deliveryThe HCH material is non-absorbing, helping to eliminate resistanceThese are designed for spontaneously breathing patients through a tracheotomy tube