The instruments are made from bamboo. The large one looks like a marimba. It is played with the hands - no mallots. The bamboo tubes are attached to the sticks that act as the mallots. So - the player just twangs the sticks and they make a mellow sound.
The pipe has holes they cover with their fingers. The holes are only on the very end of the long bamboo pipe.
Most of these things were small and in glass cases. It was not possible to get pictures.