Canon Teleconverter

[Kerro]

Canon tele-converters are only compatible with the following lenses:

1. any L-series prime 135mm or longer;
2. all four 70-200mm L zooms;
3. the 100-400mm L zoom; and
4. the 400/4 DO IS.

Works fine with my Sigma F2.8 120-300.

[Xenedis]

Works fine with my Sigma F2.8 120-300.

I'm not familiar with third-party lenses, but naturally Canon only states with which of its own lenses the tele-converters are compatible.