Amazon.com: 12V Mini Laser 250mw White RGB Laser Dot Module & 5V TTL Control Colorful Laser Module : Industrial & Scientific
4W Industry Laser 445nm/447nm/450nm 4000mW Blue Laser Dot Module Diode NDB7A75 w/ TTL0-20kHz & Fan Cooling & Long Time Working: Amazon.com: Industrial & Scientific
650nm 250mW Red laser dot module with focusing DIY - BeamQus