Western Digital on Tuesday announced the expansion of their Red line of SATA hard drives designed for home and small office network attached storage (NAS) systems. Up until now, the hard drive maker only offered Red line drives in 3.5-inch form factors but starting today, customers can pick up 1TB and 750GB Red line drives in the smaller 2.5-inch form factor.

WD Red drives are specifically tested for compatibility in NAS environments. They offer lower noise and vibration compared to regular hard drives, a boon considering their always-on nature. Red drives also feature built-in NASware 2.0 technology and error recovery controls should something go awry.

Vice president of client storage for WD Matt Rutledge said the company wanted to deliver a highly reliable and compatible 2.5-inch hard drive built specifically for small NAS. Such a drive will enable customers to use high capacity NAS hard drives with high performance, quiet operation and low power consumption in compact NAS enclosures.

Those after more capacity may be interested in WD’s new 4TB Red drive which is launching alongside the 2.5-inch counterparts. Rutledge said WD realized the need for additional capacity in the 3.5-inch form factor through dialogue with their NAS partners and customer advocacy.

Pricing starts at $79 for the 750GB Red drive and bumps up to $99 for the 1TB model. The 4TB 3.5-inch variant will set you back $229. Products are shipping now through select distributors and resellers, we’re told.