Miller replacement parts do not fit on all available MIG welders because not all welding units are made by the same company. Each brand, such as Lincoln Electric or ESAB, has specific replacement parts that fit onto the welding units.
Welding parts can be sourced out through online distributors, such as the Welder Parts Warehouse. Other options to find replacement parts include manufacturer websites. Miller replacement parts, for example, can be purchased from their website.
Lincoln Electric also has an online store where users can purchase replacement parts, consumables and new welding kits. Each item is subject to its own shipping and handling fee.