They've helped catch a lot of fleas HOWEVER, this will not solve your flea problem, only help mitigate it.  It's not going to catch all of them.  I have 3 of these.  One of them the bulb burnt out instantly but it's a fairly universal sized bulb and I had extras (it's not a regular size bulb, but the smaller one).  I do wish the bulb locked into place though, it more just hangs loosely.  I put electrical tape to keep it in place.