By Chris Nicholls

SYDNEY: Hard disc manufacturing giant Toshiba has released three new portable hard drives that hold up to 320 GB but are only 2.5-inches in length.

The USB-powered drives come in 160, 250 and 320 GB sizes, and sell for RRP $149, $199 and $249 respectively.

All three models also come with NTI Shadow automated backup software and have internal shock sensors to prevent damage to data when bumped.

Toshiba claims transfer speeds peak at 480 Mb/s and each model weighs 198 grams.

The drives are compatible with Windows XP, Vista and Mac OS 10.3.9 or later and come with a three year limited warranty.