Description :Tungsten wire, a filament made by forging and drawing a tungsten bar. Tungsten filaments are mainly used in electric light sources such as incandescent lamps and tungsten halogen lamps. The resistivity of tungsten filament is 5.3*10^-8. Tungsten has a high melting point, high resistivity, good strength and low vapor pressure. It is the best material for making incandescent filaments among all pure metals. However, tungsten is hard and brittle, making it difficult to process. When the current is heated to a certain temperature through the tungsten wire, the resistance value of the tungsten wire increases to a certain value (generally, the resistance value of the metal wire increases with the increase of temperature). The resistance of this material should be 1370℃-2000℃ at normal temperature, but this resistance value will change when the cross-sectional area and length of the tungsten wire changes. Name: High-purity tungsten wire electrode wire Purity: W≥99.99% Shipping :Items are generally shipped out without 3 Working-days business day after your payment has been cleared (Sat. Sun. excluded.) We are not responsible for undeliverable address. We reserve the right to charge the shipping fee again for returned items due to wrong address. Payment:All major credit cards are accepted through secure payment processor PayPal. If you have bought multiple items from us, you can send us one payment for all the items instead of paying for them individually. When you click the Pay Now button, eBay will automatically determine if there are other items you have won or purchased from us and will combine them for your review. Feedback:We aim to provide excellent service to our customers and build ourselves a great seller reputation on eBay. We would very much appreciate if you would take the time to leave us positive feedback after you have received your item(s). A positive automatic feedback will be given as soon as payment is made or cleared. Please choose carefully. We don’t normally give refunds if you simply change your mind or make a wrong selection. Exchanges and refunds can be given where goods are faulty, wrongly described, different from a sample shown to you or don’t do what they are supposed to. If you are not satisfied with the item(s) you received or in any service provided, we will happily reply to any message you send through email or eBay’s inbuilt message service. In this way we can try to resolve the problem before you leave us negative feedback. Contact Us:Our office hours are 9;00a.m to 6;00p.m(GMT +8) of Monday To Friday. Don’t accept return except item’s quality problem, so please check the measurement before you bid. Please contact us within 7 working days if you find the product quality problems (since the date you receive the goods), and we will do our best to resolve the problem for you! thanks! Any question just feel free to email us.usually we will reply you in 24 hours.