Forgive what may appear to be an obscure question !

I've recently started a new role with a company that doesn't provide a kitchen or brew station.

All refreshments are expected to be purchased from the company restaurant, which includes a franchise of a high street coffee brand with drinks at full high street prices.

As an avid tea drinker, this is going to be an expensive indulgence.

Personal kettles are not allowed on health and safety grounds, but the company blurb doesn't include the mini boilers which look like a kettle element and are simply dunked into the mug.

These vary significantly in build and price.

Does anyone have personal experience of these cup boilers and can make a recommendation, please ?

Cheers !