Chemglass (CG-4430) General Purpose Single Bank 4-port Vacuum Manifold. Main tube is 1" O.D. with serrated hose connection, the smallest serration is 13.5 mm and the largest is 15.5 mm. Ports have I.D. 4 mm, with PTFE stopcocks. Ports have serrated hose connections, the smallest serration is 10 mm and the largest is 11 mm (a 3/8" I.D. tubing will fit on the barbed port). The overall length of the manifold is 14" (~360 mm). Used condition, but in very good shape, no chips or cracks. Stopcocks are in excellent shape and provide a quality seal. Some cosmetic marks from previous user. 30-day money back guarantee. If there is anything wrong with the item that you have purchased, please contact us directly and give. us a chance to help, we respond quickly and will ensure you are satisfied with your purchase and experience! Please do not leave negative feedback or open any disputes with eBay or PayPal. Contact us directly and we will fix the problem quickly.Fast & free shipping We strive for 5/5 Star service! Fast & Free shipping!