Umbrella balcony fastener

My girlfriend wanted a parasol on our balcony, so I designed a way to attach one of our umbrellas to the balcony railing.

I printed the body using 20% Gyroid infill. It might be too weak depending on the weight of the umbrella and if there are any wind, but mine has held up so far. The screws were printed on their side at 100% infill for extra strength.

The handle of the umbrella I am using is 3.5 cm in diameter.
My balcony railing is about 5 cm wide and 1 cm thick but since the screws stick out about 1 cm from the bottom of the "clamp" it can be used on thicker railings too.