Toxic you only have to drill two holes. It does not weaken the skeg and if the skeg is bent you may have to work on it to get it straight. Less than 10 min. to put it on. No glue or anything else just the two bolts The only prep work was clean the skeg good and if it needs painting do it before you put the shield on. Other wise nothing to do. The instructions guide you thru the whole installation. Easy to do. I would tell anyone that has a skeg that has been damaged to go this route. Thanks for all your help.