+<li>12V Lead-Acid battery charger and terminal
+<br/><a href="power/12V%20Lead-Acid%20battery%20changer%20and%20terminal/index.html"><img style="width:100%; max-width:500px;" src="
+ power/12V%20Lead-Acid%20battery%20changer%20and%20terminal/make.png
+ "></a>
+</li>
+
+<li>battery tester
+<br/><a href="power/battery%20tester/index.html"><img style="width:100%; max-width:500px;" src="
+ power/battery%20tester/make.png
+ "></a>
+</li>
+
+<li>adjustable resistor / indicator
+<br/><a href="power/adjustable%20resistor/index.html"><img style="width:100%; max-width:500px;" src="
+ power/adjustable%20resistor/make.png
+ "></a>
+</li>
+</ul>
+</div>
+</div>
+
+
+<div id="outline-container-sec-3-4" class="outline-3">
+<h3 id="sec-3-4"><a id="ID-0ff5c7f6-e08d-4cdf-923f-3aa75d050b1c" name="ID-0ff5c7f6-e08d-4cdf-923f-3aa75d050b1c"></a><span class="section-number-3">3.4</span> Optics</h3>
+<div class="outline-text-3" id="text-3-4">