Hi All
I notice that the flash extender has recently had some publicity in threads so thought I would offer a few words of caution to existing owners and potential buyers following my own bad experience.
Saturday morning about 9am I thought I would set up the camera on the patio and take a few shots of the squirrels on the nut feeders. Set the camera on the tripod, added the Speedlight + flash extender and sat down with a cup of tea to await the arrival of my subject.
The squirrels soon arrived and I fired off the first few shots with a little fill flash, then to my amazement smoke began to pour from the speedlight. I promptly took it off the camera, switched it off and left it to cool down. After 30 minutes I put it back on to assess the damage and within seconds smoke poured out again.
Yes, you have guessed right. After an hour pondering over my misfortune and cursing Canon or were the rechargeable batteries the problem the penny dropped. Although the sun was just trying to emerge but there was still enough strength for the extender to magnify this and just like a laser had burnt a series of holes through the speedlite .
Alright I know some bright spark

will say I should have read the warning label on the packaging. Well I did but when I was setting up the light was extremely poor and with my mind preoccupied it just did not occur to check the position of the sun.
So a word of caution if you want to use this piece of kit be very careful it could prove lethal. I would urge that under no circumstances do you leave it attached to an unattended camera even for a few seconds. Worse case scenario would be to leave it set up at a window or in a conservatory you could come home to find your home a pile of ashes.
The only consolation is despite the new designer melted look and a few holes surprisingly the speedlight still works, a relief given the £300 price tag.
Think I will give the extender a miss in future.
Gerry