Hardness [Hard - Soft] Popular hardness barometer. Hardness is tested with a static hardness measurement. This measurement does not take into account the time and speed of acceleration. Elasticity [High - Low] Elasticity represents rebound force generated when a tip hits a cue ball at the speed of acceleration. When the elasticity of a tip becomes higher, the contact time of the tip and the cue ball becomes longer, so you can have more spin on a cue ball and feel the sensation of a bouncy shot. On the other hand, the contact time is shortened when the elasticity decreases. So that you get a more solid feeling of impact.Translated with www.DeepL.com/Translator (free version)