Useful Links
International EPR Society
Advancing the field of electron paramagnetic resonance
EFEPR
The European Federation of EPR groups (EFEPR)
Unit Converter
All necessary stuff to survive inside and outside of the lab.
RF Calculators
Easy to use tools for radio and microwave frequency calculations and conversions.
Spin trap database
Very useful link
Shared EPR
Another useful community
Easy Spin
A powerful solution for those who dealing with the simulation of EPR spectra
Optical Tools
Edmund Optics® Technical Tools. Useful calculators.