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: Seagate Barracuda ATA IV 40GB UDMA/100 7200RPM 2MB IDE Hard Drive
Product description: Add 40GB of fast, modern storage to your computer with this refurbished Seagate hard drive! Featuring fast UDMA/100 data transfers and a 2 MB buffer, the ST340016A is ideal for extra storage space. Seagate Barracuda ATA IV 40 GB UDMA/100 7200 RPM 2 MB IDE Hard Drive Product Requirements IDE controller IDE cableAvailable 3.5-inch drive bay Available 4-pin power connector
Product feature: Seagate Barracuda ATA IV 40 GB UDMA/100 7200 RPM 2 MB IDE Hard Drive General Features:, 40 GB formatted capacity 7200 RPM spindle speed 2 MB buffer 9 ms average seek time 4.17 ms latency, UDMA/100 data transfer rate E-IDE/ATAPI interface Regulatory Approvals: CE UL CSA MIC C-Tick
Product brand: Seagate
Target attributes: Form Factor
Answer: attribute: form factor
value: 3.5-inch
source: product description