One end of the Amazon Dash Wand has a barcode lighting-and-scanning assembly protected by a plastic lens.
The unit, as with other equipment for which some degree of protection from moisture and other environmental factors, not to mention from consumers, is desirable, was ultrasonically welded. Persistence, elbow grease, and the combination of a narrow flat-head screwdriver and a box cutter will get you inside.
On the left is the magnet cluster that enables the Dash Wand to cling to a refrigerator or other metallic surface. On the right is the barcode reader assembly, and underneath it is the mono speaker, connected to the system board via twisted-pair wiring.
Here's a closeup of the system board. In the upper right corner is a Wolfson Microelectronics (now Cirrus Logic) WM8904 audio IC for driving the speaker and handling the microphone input. The microphone itself is on the far right, next to the QR code sticker. At the lower right corner, below the WM8904, is the speaker's twisted-pair connector. In the middle is the main system processor, an Atmel (now owned by Microchip) ATSAMG55J19A-MU ARM Cortex-M4-based microcontroller. In the upper left corner is Texas Instruments' TPS61091 3.3V-output boost converter. And in the lower left corner is a Micron M25Q128A serial-interface NOR flash memory.
On the back of the PCB you can see the switch controlled by the device's button, surrounded by four LEDs (D60-D63) to selectively illuminate the ring around it. On the right edge is an embedded trace-etched antenna; additional embedded antenna structures are above and below it. The PCB hole just to the left of the main antenna matches up with the microphone hole in the case, and on the other side of it is the previously mentioned microphone. And to the left of it are (above) a Microchip ATWINC1500B Wi-Fi controller module and (below) a Cypress CYBL10563-68FNXI Bluetooth Low Energy chip, used for initial setup.
Pry the speaker housing away from the barcode scanner assembly and the speaker itself comes into view.
Remove the speaker and the guts of the barcode scanner come into clear view. On either side are illumination LEDs, with fresnel lenses in front of them. Between them is another lens assembly, this time for handling reflected-from-scanned-object light travelling in the opposite direction. And behind that lens is a linear-scanning image sensor.