You can see how it works in this short clip on my instagram page here.
The Eerder Stoppy bar is compatible with all the Brompton luggage frames (except the electric ones) and the Trigo version available here.
The Stoppy bar prevents your Brompton bag from falling forward. This tipping over is caused by the small angled foot in combination with the inbalance caused by the stuff in your bag and the flexiblitity (lack of stiffness) of the bag. The stiffer waterproof bags like the Metro and the Borough suffer less from this, but still it might happen. You know best if you will benefit from the Stoppy bar or don't need one. But with it your bag will certainly not tip over anymore.
It comes in two different lengths: short and long. The short one is 136mm long and the long one 166. This length is also the stickout from the front of your front carrier block or the corresponding face of the luggage frame. So you can check your bag to know which one would fits best. If you don't mind or enjoy seeing the 'happy face' cut out at the end of the Stoppy bar than you can also choose the long version although your bag is for instance around 135 mm in depth.
The Stoppy bar comes with all hardware required and two thick rubber O-rings to act as feet to stand on and to be added to the 'çorners' of the luggage frame. The O-rings make your bag stand even more stable and protect the fabric of your bag and the aluminium of the luggage frame.
Assembly: A few fairly simple things you need to do. Ask a handy person in case you don't trust your skills. The Stoppy bar comes pre assembled so it's clear what should be where:
Specs:
size: 166 or 136 mm long and 63 mm wide
material: 3 mm thick 304 stainless steel, stone tumbled for a nice RAW finish
including stainless steel fasteners and two rubber O rings
weight : 114 gram for the long Mk2 and 107 grams for the short Mk1 version including rubber parts and hardware