0.06 mm Enameled Round Copper Wire thermal class: 240 °C (Class HC) is a magnet wire with the copper conductor in round shape. It's an essential part of winding for electric appliances. 

Material: Copper
Color: Natural
Gauge: 0.06 mm
Thermal class: 240 °C (Class HC)

Magnet wire is copper wire with a thin layer of insulation, and it is used in a variety of applications including transformers, wound coils, motors, solenoids, and instruments. Raw copper is drawn to meet specific size requirements based on National Electrical Manufacturer's Association (NEMA) standards. This magnet wire meets the NEMA MW-16-C standard for operating temperature (240°C/464°F) and insulation makeup. The insulation is made from polyimide, which protects the coiled wire from short-circuiting.

Properties:
(a) good electrical properties like few pinholes under high voltage, 
(b) resistance to mechanical stress, 
(c) excellent heat, chemical, solvent resistance, 
(d)  abrasion resistance, 
(e) long thermal life and  
(f) long corona resistant life for model EI/AIWCR/200, etc. 

Some uses besides Crystal Radio Coils.
Generators and Alternators
Motors AC, DC, Hermetic and Fractional Integral HP Motors
Power Tools, Solenoids
Dry Type Transformers, Class 105 through 200
Electronics, All Types of Coils, Class 105 Through 200
Arts & Crafts
Inductors