The Roth handlebar design is very nice. Very few scooters have detachable handlebars, and this is a very nice feature for stowing the motorboards under a bus or train seat.
The T-Stem and handlebars are the same for all models of motorboards. The T-Stem will fit all steering columns for all models. However the handlebar dimensions have varied slightly so that the T-Stem and handlebars come as a matched pair, and must be used together.
The disadvantage however is that the handlebars, when detached, dangle and can be a nuisance. I found a simple solution to be to carry a rubber band with me. Connect the two handlebars together by means of the rubber band under the main steering bar. When I am riding the motorboard, I simply leave the rubberband on one of the bars.
Careful of the pin
One important note: The detachable handlebars are held in place by a spring loaded pin. If that pin is NOT properly in place, the handlebar will detach. If it detaches during a kick-scoot, where your weight is pressing fully on the handlebar to give the motorboard extra speed, you will quickly find yourself tumbling onto the sidewalk or where ever.
Repair the elastic band
After about five months of use (5x20x2 or 200 rides) the black elastic band inside the handlebars wore down and broke. I was able to replace it easily with simple elastic cord. I doubled the elastic cord to provide strong pull so the handlebars wouldn't bounce, and tied a knot in the ends at the end of the handlebars.