$5.99 for salad or burger at Red Robin

Red Robin has the Chophouse burger w/ unlimited fries and their Southwest Chicken salad for $5.99. Normally I think it's around $9-10. Get those two go for a quick dinner for two after work.. It's on the frontpage at www.redrobin.com

Is this for a certain time of day or days of the week? I went to their site but didn't see a mention of it.

it just says for a limited time; it shows up right on the main page.