12V DC 30W 78Wh 6500mah Rechargeable Lithium Ion, Li-ion Portable Battery Pack, Power Bank for CCTV Cameras, LED Strip Lights and more. With UK Plug Charger

So far so good. Used this to power a Celestron AVX 6" SCT Go To telescope. The AVX is power hungry but at the moment it seems to hold up well. I've not tested it till the battery runs down but I think it makes a good power tank for this purpose.

I use this to power a 7" monitor while videoing sport. has not given any trouble, I would love if there was a way to know how much power is left

It did not work. Sent it back for a refund.

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Useful for my project