I thought we'd made our point to the Chinese suppliers that these filters are unsafe and should be removed from sale.
Now they seem to be back!!
http://www.ebay.com.au/itm/Optical-L....c100009.m1982
https://www.ebay.com.au/sch/i.html?_...ilter&_sacat=0
You can help save the sight of some poor child or novice by posting this message on their link:
These sun filters which fit to eyepieces have been found to be unsafe and could cause serious eye damage.
In a telescope, the solar energy is concentrated onto the filter and can cause it to crack or shatter.
These should be withdrawn from sale.