Thai Police Clearance Certificate From U.k

Have any members done this from the U.K? I sent all the required documents yesterday to Bangkok.

Tried to get some information from the Thai embassy in London, Bob hope and no hope. The one thing that concerns me is that you must provide an envelope with pre-paid stamps, for them to send back to the U.K???????

BRITISH stamps from Thailand....? how do they do it?

I would be glad of any information regarding this matter.

Thanks.