Just recieved this email.
I am very sorry to hear about the problem you are experiencing with our new Tornado Kit 04924. I have contacted our QC department and have discovered that this was a manufacturing error.
The part is missing in all kits being produced.
The purchase department has stopped all further orders and requested a separate production run on the clear part including part 173 now.
I will receive the parts here in Tring and post them out to you as soon as possible.
Please feel free to contact me with any further questions.