The ApneaTrak™ PVDF Effort Belt provides accurate measurement of respiratory effort and maintains polarity. Low profile buckles ensure patient comfort and quick, easy set-up. Durable, machine washable straps. No need to change batteries. Also available in a three channel model with a summation channel that shows true paradoxical breathing. Complies with the Respiratory Rules Section of the AASM Scoring Manual. We’re so confident in the durability of our Perfect Fit Effort Belts, that we offer an unprecedented 2-year warranty. Latex free.