For all who have for example the Tahoe model, which is normally delivered without the brake. One could easily upgrade it to the 2-in-1 trailer and stroller model. Disc brake is actually a set – it´s the mechanical disc brake Avid BB5, the disc Avid 160 mm, brake cable and a brake lever with manually adjustable arrestment.
You could of course additionally buy also the two-wheels axle with 12 inch wheels to complete the transformation from a trailer to the 2-in-1 trailer and stroller.