There tweezers grades ： (precise tip measurements for each tweezer is given)

．Biology ： smallest, sharpest points

．High Precision ： for needs which do not require the sharpest point

．Electronic ： normal manufacturing operations

．Style PELCO EMX ： Designed for EM grid handling

．Point Sizes/Sharps ： listed by each tweezer, example ：
- Super-fine ： style 5
- Extra-fine ： style 4
- Fine ： style 3, 3C , 7

．Major metals are ：
- DS ： newest, hardest, non-magnetic, corrosion-resistant steel, DUMOSTAR
- SS ： stainless steel next hardest after DS., harder than NM
- NM-SS ： non-magentic stainless steel

．Other materials or coating listed ：
- Carbon Steel ： very hard point
- Carbon Fiber ： non scratching, soft, acid resistant, conductive, non-magnetic
- Ceramic ： chemically resistant, nonmagnetic, non-conductive
- Titanium ： very high chemical resistance, tough, non-magnetic
- PTFE ： high chemical resistance