diff --git a/toroid.html b/toroid.html
index b1c6008..1233d26 100644
--- a/toroid.html
+++ b/toroid.html
@@ -98,8 +98,9 @@
                 <li> Rw(&#937;) : (PI) - Resistance due to wire losses in Ohms. </li>
                 <li> Q : Quality factor. (X/R) </li>
                 <li> I(mA) : RMS current in milliamps. </li>
-                <li> &#956;'  : Complex permeability - reactive part. (Hidden by default.) </li>
-                <li> &#956;'' : Complex permeability - resistive part. (Hidden by default.) </li>
+                <li> &#956;'  : (F) Complex permeability - reactive part. (Hidden by default.) </li>
+                <li> &#956;'' : (F) Complex permeability - resistive part. (Hidden by default.) </li>
+                <li> &#956;   : (PI) Permeability (Hidden by default.) </li>
                 <li> H(Oe) : Core field intensity in Oersted. (Hidden by default.) </li>
                 <li> B(G) : Core flux density in Gauss. (Hidden by default.) </li>
                 <li> Pd(mW) : Sum of the power dissipation in the core, in milliwatts. For PI, it includes power dissipated in the wire also. </li>