Kill Cockroaches

Assuming you are talking about the smaller German roach found living in the cabinets and appliances….I am not sure what the active is in the raid roach gel, but Combat roach gel is made by the same people who make the professional brand MaxForce. Avoid using any other insecticide / chemicals near the baits. The bug sprays, boric acid and many cleaners used in insect control act as repellents. The roaches need to eat the bait for it to kill them and the next generations. I have not used the combat myself (Maxforce is stable in my business) but quite often when I have people who work for my customers ask what they can get this is what I suggest and in the many years that it has been available I can not recall anyone coming back to say that it didn’t work. You can also buy maxforce yourself from a do it yourself type pest store..at a pest control supply house or over the web.

Unless you sinks are not used for long period of time, they are already closed off from water in the trap under the sink, no real need to do anything special around them to block roaches from appearing.