Solder heat shrink butt connector opinion

Hi everyone. I've used solder heat connectors on a multitude of devices that pull little amps. Say eBikes, fans, etc. They are very easy to use and the work is solid.

From the website, they say they're rated up to 600 V, but nothing about watts or amps.

I live in Europe, so it's 220v.

I'm equating if this can be used in a 1000 watts heater. That would be around 6 amps.

https://preview.redd.it/rq2awb2x4kme1.jpg?width=1920&format=pjpg&auto=webp&s=57903ddfc9fc7ad45d299574961c08e6b963636e

https://www.partex.co.uk/cable-accessories/crimp-terminals/connectors/solder-heat-shrink-butt/cid,5b87cad641d4e72bf09f4200

Any experience? Any advice on how to twist the cable?

Many thanks for your guidance!