Sturmey Archer DLS40 Trigger Shifter

Good but not perfect mainly due to the reach/distance that you have to push with the thumb is relatively long for the small hands;
shifting up with the index is great,
shifting down from 4-3 and 2-1 is OK (not perfect), but
3-2 is honestly rather difficult (even for me) as one have to push hard to the very end for the gear to shift up - and my son of 6 years does not have fingers/thumb long enough to push it to the end unless removing the hand from the handle (=I tried and it is just the distance of a female hand but you really have to push hard).

The Belter has a gripshift that my son couldn't operate due to the force needed to shift to lighter gears. I replaced it with the trigger shifter and my son can shift up now. So it shifts with less force . However, the lever throw is crazy long for the tiny hands. So my son now shifts with his full hand on the shifter. Okay for quiet streets, but not so for when it's busy or in forest. So surely not ideal and useless for the intended use of the bike. Yet still better than the gripshift.