Instruction: Parse the product information to locate the target attribute, and then provide the extracted value of the target attribute and its source in the output, specifying None if the attribute is not present.

Input:
Product title: Premiertek 8-Meter Low Loss RP-SMA Male to RP-SMA Female RG58/U Coaxial Cable (PT-SMA-EXT-8)
Product description: Low Loss RP-SMA Male to RP-SMA Female RG58/U Coaxial Cable 8 Meters 26.3ft
Product feature: RP-SMA Male to RP-SMA Female, RG-58U coaxial cable length: 8Meters (26.3ft), Gold-plated body and gold-plated center pins, 50ohm, Conductor Material: Copper Clad Steel, Shield Material: Bare Copper Braid, Insulation Material: Solid Polyethylene
Product price: $2.54
Product brand: Premiertek
Target attributes: Audio Channels
Answer: attribute: audio channels
value: None
source: None