How do I combine '.zip.001' files?

Hi, So I've got some files I need to combine that look like this: sample.zip.001 all the way through to sample.zip.017 I can't work out how to unzip them. I've tried WinRAR, 7zip, HJsplitter and Master Splitter. Most of them seem to unzip fine, but when I look at the new .zip file, it only comes up with a dummy file named .DS_Store Is there an obvious way to fix this, or is this a fake file? Easy 10 points right here