Hello Guocheng, If you need just small amounts of tubing, visit a local hobby shop. They sell brass and aluminum tubing in various diameters in about 12- inch lengths, and it is relatively inexpensive. I believe they are commonly used for gas engines on model airplanes. Brad Cantos brad.cantos@holage.com http://holage.com On Jun 28, 2009, at 11:58 PM, Shao Guocheng wrote: > Hi, all, > > I'm working on some microfluidic device with pneumatic micro > valve. We normally use plastic tubing from upchurch for microfluidic > chips. But it might be a little easier to form air-tight connection > with metal tubing. I have seen some in the literature, but cannt > really find the supplier..... Did some goolging but got no luck.. > > If you happen to be using metal tubing for microfluidic chips, > would you pls provide me some information about where I can get > these tubings. I will need something with OD around 1mm.