How do I put the tips into a Eurotool flex shaft?

I bought a eurotool flex shaft and a hammerhead but i cant figure out how to screw them into it. It makes no sense.

ok, i am not sure if i understand your question, but here goes…

re the flexshaft hand piece #30 jacobs)
there is a 3-jaw chuck on the business end. you use the T shaped chuck key to open and close/ tighten the jaws, around the various bits…the teeth on the chuck key “seat” perpendicular onto the teeth around the jaws…there is a U notch where the key goes……you turn the key and the jaws open and close

re the flexshaft quickchange handpiece:
there is a lever in the handpiece which opens and closes the jaws (only fits 3/32” bits). i have a quickchange handpiece where the jaws sometimes sticks in closed position around a bit after i open the lever…i have to tap the bit into the bench pin to get it to release…i bought a cheaper shorter quickchange handpiece recently…the jaws got stuck the first time out…my trick to release it did not work…tech said it wouldn’t…i returned it…

re the hammer handpiece:
the hammer point screws into the business end…there is a little hole on the shaft of the hammer bit…they usually provide a small metal tapered stick…you put it in the hole to give leverage when tightening the bit…it give you something to hold onto when tightening

re the other, more open end of both the flexshaft handpiece and hammer handpiece:

if you look down into the open end of the handpieces, there is a tube down in there, with a slot/ notch…a mini maglight helps see in there…

now, if you look at the free end of the shaft hose itself, you will see a metal tip sticking out, that has like a key tab

that tab fits the slot…

one way is…without pressing the footpedal, you can look into the open end, determine the position/ location of the slot, and then take the key end of hose, and line up the key to the slot…you can push it slowly in…it will either go into the slot…or it will feel like it is hanging up on the edge of that tube as you gently push
the key needs to seat in the slot…then you push the hose in more firmly

you are holding the hose near the key end

another way is while the key is spinning/ you are stepping on the footpedal…see below video

i hope that helps

better yet, you can call eurotool customer support…

there are how-to videos on youtube