This is a S-Hook for your (bathroom) heater radiator, designed by me in OpenSCAD.
Alternatively, you can use the hook on any object where either hook can be attached to.
So heater radiators are not
Because both hooks are slightly offset the hook will not easily slide of the radiator tubes.
Likewise, any object hung from the (smaller) hook will not easily slip off.
When printed in PLA and with just 30%-40% infill, the hook is still strong enough to hold objects up to 12 Kg (26 lbs).
When your radiator gets very hot, it might be preferable to print the hook in another material like HD-PLA, PETG, NGEN, XT or ABS.
Mankati Fullscale XT/XT-Plus
This is an easy print.
No support or rafts are necessary.
When printed with 30%-40% infill or higher, the hook will easily hold weights of up to 12 Kg.