Deep vacuum cups are used for highly curved or irregular surfaces and can even seal against corners, edges, and spherical
workpiece. Deep vacuum cups are unsuitable for use on flat surfaces because the lip will be overstretched and the
resultant scrubbing could leave marks on the workpiece.
SILICONE (50A) has a very wide temperature range and is suitable for both sub-freezing applications and for elevated temperatures. Silicone is inherently more supple than other rubbers so it may seal better on textured surfaces.