int npcId = npc.getNpcId();
int cond = st.getCond();
if ((npcId == STONES) && (cond == 17))
{
st.playSound(SOUND_MIDDLE);
st.takeItems(DETECTOR, 1);
st.giveItems(DETECTOR2, 1);
st.setCond(18);
player.sendPacket(new ExShowScreenMessage(NpcString.THE_RADIO_SIGNAL_DETECTOR_IS_RESPONDING_A_SUSPICIOUS_PILE_OF_STONES_CATCHES_YOUR_EYE, 4500, ScreenMessageAlign.TOP_CENTER));
}
return "";