I attach a print from www.amscousa.com who do not supply outside US showing sizes plus a photo of my existing part from my Ducana window. I was looking at parts
26-078 and
26-079 in white which might be suitable and less expensive than
26-188W. I need 6 of each of the nylon parts if you think they are suitable. If you need further information, please let me know. Once I hear from you I will place an order to send to Scotland, UK. Thanks