What sets TSR20 and TSR10 apart from one another? TSR 10 & 20: The most widely used and widely accessible grade of TSR in the market is TSR 20. Similar qualities are found in TSR 10, albeit it is cleaner in terms of dirt and ash. Compared to RSS, TSR 20 and TSR 10 will both have less viscosity and be simpler to combine and masticate. Technical Specifications Rubber TSR 20, sometimes referred to as block rubber, is rated based on exact technical factors such the amount of dirt, ash, nitrogen, volatile matter, and rubber characteristics like Wallace Plasticity (PO) and Plasticity Retention Index (PRI).