This is tiny camera/VTX combo mount for 16x16mm setups. I use it with this camera: https://aliexpress.com/item/AKK-BS2-5-8G-48CH-25mW-VTX-600TVL-1-3-Cmos-AIO-FPV-Camera-for-FPV/32804924139.html But most likely it will fit popular VM275T: https://aliexpress.com/item/VM275T-Upgrade-Ver-HC48-5-8G-25mw-48ch-Picture-Transmission-Integrated-FPV-Camera-w-Magnesium-Light/32821847503.html I printed it with ABS and camera goes inside veri tight - be carefull. Probably if printed with some FLEX - it would be better - more easy to install, more secure against crashes...

Updates: (12 Oct 2017) Rev4 - added some vent holes... (10 Jan 2018) Added separate Base and Cover models...