Robert Phillips wrote:
I am looking for a reliable convert to plug a 300W 120V US fan heater into a UK socket.

The plug looks like this

http://a-bike.co.uk/wp-content/uploa...13001438_S.jpg

Maplin have a converter that does 300W for £40 but it's a bit risky as it gives no leeway.. I think the convert should support e.g. 400W or 500W.

I suppose it's a step up voltage converter that I need. According to maplin.

Look for a 'site transformer', often used on building sites to run 110v
tools from 240v mains. You can often pick these up for cheap in variable
cosmetic condition from local ebay/gumtree/etc - they're heavy so it's
cheaper than posting.

You'll need to make an adaptor from the US plug to the bright yellow BS4343
site connectors, or rewire the plug.

Watch for the continuous rating - often the nameplate rating is only
intended for short periods when running power tools.

Theo