This is an original Thayer and Chandler airbrush air valve spring in excellent condition that i acquired in a lot of vintage airbrush guns and parts. This is for one piece. I believe they are all pre 1960-50s. I have taken approximate measurements to help identify if this may be a part you need or want. It is 1 cm tall X 3 mm round.  Makes a really cool addition if you just a collector too. Please feel free to ask any questions prior to purchase.