While installing fairy lights into our Kitchen strip-light last night, my housemate (an electrician) was baffled after removing the metal base; he found a strange device connected to the live feed by two black wires. He cut it out with no adverse effects on the light function. We've lived in this house for just over a year and judging by the various placards etc. we've found in the garage & cellar, the previous tenants were active Socialists.

The device is about an inch across and 1/2 an inch in length, with a thickness of less a quarter of an inch. It is made of grey plastic with a base of black plastic. Two thin black wires protrude on either side of the base. It has written on it the following info': DNA MKP41 0.047uF M 40/100/56/c 275v-250v-. There's a triangular symbol with numbers underneath: EN132400 Then a circular symbol with a black figure in it (looks a bit like a bird with outstretched wings), then the letters CE followed by a reverse R and U. Is this a bug?

From your description this appears to be a common noise or harmonics suppression capacitor in your use of it - also used for different purposes in other electronic circuits. The .047uf is the capacitance rating and the 275v/250v are the max voltage rating.

This is a common device made by various electronic mfgs... e.g. TDK... Okaya.. etc.

I found this number in my electronics parts catalog (EN132400) - but you can also Google it for more detailed data.

On the other hand it may be a bug disguised as a capacitor lol if you're so inclined - hope this helps.. RG