Pistol Magazine Shape 90rd Speed BB Loader
[AS2089]

It's what you can expect for a cheap loader. Its not great build quality but it will do the job.
It loads 4 BB's with each push, so if you can count in multiples of 4 then you can decide how many to load into your mag.
Small issue sometimes needs to be wiggled in order to keep the BB in chamber moving into feed. But again it is a budget loader. I was happy with it for the price.