It's a big wall hook.

It's a big hook. Inside span is roughly 100mm, and it measures approx 115mm high x 25mm wide x 120mm deep.

It's fairly strong as can be seen in the picture where two have been holding a 5lb pickaxe for many months without so much as bending, but I still wouldn't put TOO much weight on it.  Its a great hook for bulky but not terribly heavy items.  I have several in use in my garage for various garden items and even a couple shovels with zero issues.