SaveMyLight are the only UK retailer of replacement Hytec lighting transformers.
Hytec have really upped their game over the last year. Having visited their new factory in Guangdong and seen their process for manufacture and Quality Control it is a pleasure to sell their products.

The Hytec HY-3360D is a twin rotary dimmer that has 2 x 240v outputs.
Output 1 is controlled via dimmer switch up to 300w.
Output 2 is controlled via dimmer switch up to 60w.
This transformer fits directly into lighting luminaires.
Both outputs are controlled by rotary adjustment.
The HY-3360D is not compatible with LED bulbs.

The Hopestar LD-901 & LD-902 are also replacements for the HY-3360D. A slight modification to each output will need to be made by swapping the output wires around due to the maximum wattage of the Hopestar models. It is a simple case of swapping O/P1 and O/P2 wire around.