If you are from USA or any other country, which laws doesn't allow to play online casinos, and you trying to play free slots no download.
Some casino software providers like Microgaming, IGT and others does not allow players from restricted territories to play online slots even in Demo mode. You will see a screen like that:
There is a solution for you:
To play that casino games no download from your home you can use any online anonymizer, which uses UK Server. There are plenty of it on the net.
For example SecurityKISS - is a free VPN service. You just need to download the free software, choose any UK server and enjoy playing online slots no download from your home.