Crimping irons or crimpers work by crimping hair in sawtooth style. Some pliers are equipped with a crimping tool for the purpose of compressing crimp connections. Crimped connectors are less expensive but require a specialised crimping tool. Copper pipes are typically joined by soldering, brazing, compression fittings, flaring, or crimping. Wires may be attached to male or female blade connectors by either crimping or soldering. The crimping is usually accomplished with special crimping tool such as crimping pliers. A rivet compression or crimping tool can also deform this type of rivet. Connectors are typically attached by crimping, though soldering is also possible. Wires are attached by means of solder, crimping or insulation displacement. Handheld tools (sometimes called "crimping pliers") are most common, which may be ratcheting. It is then sulfonated and made into staple using conventional crimping and cutting techniques. Pneumatic and hand-operated cap-seal crimping tools are available. The new problem is the "crimping of electrical connectors" causing new production and delivery delays. Washing, stretching, drying and crimping complete the processing.