The katha for the amulet is powerful. If misuse wrongly, instead of inviting helps from deva or gods, you might invite the wrong "thing" and get the wrong result. We will only give katha chanting if the monk himself provide us with the suitable katha and give specific instruction on how to use. Some amulet does not require chanting as it is already properly blessed by the monk himself and have energy in it. Just wear with faith and you can feel the different.