Yes now days Google panda damage lots of sites. We must keep the unique content and high quality sites.
This is just because of Google algo updation, so do your work regularly & you will again good ranking.
I think your website is low on the content side. SO you need to add more contents on your website pages to get the lost results after panda update
Maybe it has something to do with your content. or with the way you build your links. I've seen your site and thought that your articles their are not informative enough. Anyway its only my opinion. Hope that you will find what really is the real problem of your site.
Its because your website has duplicate content... In fact most of content is copied from other sources. Your website is hit by panda for sure. Since its about features and specification of products you can do much about it, But still you need to rephrase the description of the products, jumble its specification... May be it can work for you... Good Luck!
My site got hit hard a couple weeks ago now. Some people pointed to some real reasons for it, but others said not a problem. One thing I noticed is other people had copied off my text to make blog articles. So nothing I could do but create new content, which I did. I fixed the other stuff too in case it was an issue, and now I wait to see the outcome.
If there is drop in PR -> Its usual, pr always fluctuates a lot... If there is drop in traffic and is high drop for a days -> it may be due to google's panda update..
It could be that you might be experiencing "Google Dance" where your site goes in and out while Google searches for a permanent position for it
Why don't you focus on driving new links to your site? Screw your rankings, build up your content, and build other traffic sources.
I think that you shouldn't worry on the negative things that is occurring to your site. Find ways and work on the things that you have control.