The stability of nail-free glue depends on the object being secured. On flat surfaces, nail-free glue is very stable and can hold objects securely. However, on rough, shadowy, or uneven surfaces, the stability of nail-free glue is not guaranteed, potentially causing the object to fall.
Therefore, when using nail-free glue, it is important to clearly identify the type of object being secured and the surface conditions to ensure stable attachment.
