Its a simple internaltwist lock friction clamp and it doesnt spin when closed. Current offering is 19ft -21ft actual, it will shortly have a 5ft top extension and later a 3ft base extension.
Here are some unfinished notes on the history one pole I sold has been in continuous use abroad for 3 years on trial.
"June 4th 2007
The modular carbon fibre Map F16 is ideal for high work over 30ft but many readers express an interest in cheap poles for lower work. Some years ago I made a wfp from a telescopic whip fishing pole and stuck a brush on it. I got to 18ft and it promptly collapsed as soon as I started to work with it. I could not get it to stay up.
Revisiting this chain of thought about 2 months ago I bought 3 different makes of telescopic and modular flag/kite pole and re started work. The glass fibre sections are slightly bendy but because they taper are lighter than current parallel section wfp. They are available world wide.
I have been encouraged by users who have bought the Ron Thompson Zensorflex –designed for use with the F16 carbon fibre, and used it as a modular wfp at £18 it is very strong but a bit whippy compared with the carbon fibre which is a delight to use. Also the Gangster which at 27ft is ok
Pac Hawk 9m 1022gm/2lb4oz reaches 18ft . collapse.
Spirit of Air 10m 911gm 2lb10oz reaches 21ft + body height.Collapse.
Sky Blue poles. Collapse.
You put the poles up by simply but forcibly extending to the stop and giving a slight twist to lock. When I used them previously I had a 16oz brush and as soon as you knocked the top it would totally collapse in a concertina fashion. Which is useless but I persevered. I have since then used lighter brushes and this is fundamental to their use. They are designed to be used with a flag which has no weight and if you add a slight induced bend as with a windsock they will stay up for a long time. I marked the circumference of each pole when extended by scribing around each section where it joins and then seperated them all. If you do this you will find there is a generous overlap with the Paqc Hawk but not so much with the Spirit of Air and the xxxxxx When extending you now have a marker and an idea of where the inner butt section finishes and how hard you can pull to lock the pole when in use.
Tbc.
As you see I have revisited the topic of 2007 and obtained after 3 years searching a collection of poles - and a pole that stays up from China. For those that may have missed the 3rd video here is a link. Scroll down.
http://robinson-solutions.blogspot.com/2010/08/q-with-electric-window-cleaner-jeff.html