i. Inner Diameter of coils( ID ): 10mm, 15mm, 19mm, 22mm, 25mm,50mm, or custom-made, no extra charges ii. Cross section of elements: 1.5mm, 1.8mm, 2.5mm,3mm, 3.5mm(round); 4x2mm, 4.2x2.2mm,(rectangular); 3x3mm, 3.5x3.5mm(square). iii. Outer Diameter of coils( OD ): OD= ID + Diameter of cross section x 2 iv. Times of coils, usually, divide the length of the whole coils ?¡ãL?¡À, with the diameter of the elements, you get the times. For example, L=30mm, the diameter of the element is of Dia. 3mm, you get 30/10=10 times. That is under the condition that there is no space between coils, if there is, the times should be fewer. It is up to your decision. v. Length of the cold end L: Standard 45mm, you can make your choice. vi. Voltage and Power are at your decision vii. Lead wire: high temperature Teflon wire(200??), Fiberglass wire(400??), SS(Stainless Steel) braiding is available for choice. viii. Thermocouples optional: Type K and J