These red and black lines have a .025" diameter. See the sizing table below to determine the real world size at your scale.
They have a solid core and will bend easily without kinking. It can also be straightened out and is firm enough to hold its shape.
Depending on your scale, typical uses are large battery calbes, small to medium coolant hoses, heater and A/C hoses. Can also be used for larger electrical wire.
Equivalent 1:1 sizes at each scale.
1/16 scale = 1/4"
1/12 scale = N/A
Each package contains two 18" coils.