Aim Sports PJBS12G Laser Bore Sight 12 Gauge 635/655 nM Wavelength
https://www.tandktactical.com/shop/815879011596-aim-sports-pjbs12g-laser-bore-sight-12-gauge-635-655-nm-wavelength-11459
https://www.tandktactical.com/web/image/product.template/11459/image_1920?unique=827157a
These Cartridge Laser Bore Sights come in many different gauges and calibers. They have a brass case and a 5mW red laser.
