Measure from small ring at the bottom of eye under the ring, this is where your curtain clips into.

Measure your recess and then add on 15cm on either side. For acoustics , we recommend further to fully cover the window and the surrounding area. In our test we added an additional 30cm to the width and also made the curtain floor length.

Each rail is made of strong aluminium which can be forward and reverse bent by hand to cater for all angle multi sided bays as well as straight windows. All lengths can be trimmed down at home using a fine tooth saw if required. The measurement from the top of the profile to the bottom of the hole in the glider is circa 3.4cm.

I struggled to get the rail attached properly to one of the supports next to one 90 degree curve, and the curve does seem quite tight even though I used the slightly wider imperial measurements in the instructions for placing the supports at the corners. This in turn has led to the curtain catching slightly going round that curve.