Hi Peer,

Thanks for the tip, I was unfamiliar with the tags. They make a big difference for the viewer!

The lines I added were simply data for more materials starting at line 501.

The "optgroup label" is the category name
The "option value" number is Kg/m^3 which is followed by the material name.

Note: in some cases the values I've added are average values for a class of material. There are so many manufacturers with custom items that the list would become unnecessarily long for a very insignificant density delta in most cases.

<optgroup label="Electrical" value="">
	<option value="3600">Alumina</option>
	<option value="3050">Lo-Temp Co-Fired Ceramic</option>
	<option value="3600">Alumina</option>
	<option value="3210">SiC+Binder Preform</option>
	<option value="1850">FR4 (Averaged PCB)</option>
	<option value="887">Metallized PP Film (Caps)</option>
	<option value="1000">0.3W/mK Epoxy</option>
	<option value="1270">1.2W/mK Epoxy</option>
	<option value="2000">1.1W/mK TIM</option>
	<option value="2700">1.8W/mK TIM</option>
	<option value="2900">2.0W/mK TIM</option>
	<option value="3000">3.6W/mK TIM</option>
	<option value="1800">Coolpoly D5506</option>
	<option value="2700">Al Conductors</option>
	<option value="8890">Cu Conductors</option>
	<option value="8845">Cu Terminals</option>
	<option value="8730">CuNi18Zn20 Shielding</option>
	<option value="960">PE Wire Insul.</option>
	<option value="1230">PUR Wire Insul.</option>
	<option value="2150">PTFE Wire Insul.</option>
	<option value="1400">PVC Wire Insul.</option>
	<option value="2000">Teflon (FEP) Wire Insul.</option>
</optgroup>
<optgroup label="Motors & Inductors" value="">
	<option value="8850">Magnet Wire, Coated</option>
	<option value="4750">Ferrite Core N49</option>
	<option value="3600">Ferrite Core PC90</option>
	<option value="7400">Nd-Fe, Sintered (Avg)</option>
	<option value="8300">Sm-Co, Sintered (Avg)</option>
	<option value="7650">Laminate e-Steel (Avg)</option>
	<option value="7200">Finmet Alloy Ribbon</option>
	<option value="8700">Mumetal Alloy Ribbon</option>
	<option value="1150">Nomex 4-10</option>
	<option value="1430">Polymide Apical AV</option>
	<option value="1420">Polymide Kapton</option>
	<option value="1780">PVDF</option>
	<option value="2150">PA/66 & PA66</option>
</optgroup>