Most of us use 'push-sticks' to help when cutting and routing timber but there are some cheap and nasty plastic push sticks on the market these days that can shatter or break and cause potentially very nasty accidents in the workshop. If you are looking to buy one choose a shatter/break proof version and make sure that it is advertised as such. Axminster sell good ones. Market stalls don't as I found out by nearly losing several digits!