B4 2/3" HD adapter with glassway for projector with CLC-base
B4 (2/3") ENG Cine Lenses to C-Mount Cameras - Pro Lens Adapter – Fotodiox, Inc. USA
Used Blackmagic Design URSA Mini Pro - B4 Mount | MPB
Amazon.com : Fotodiox Pro Lens Mount Adapter - B4 (2/3") ENG Cine Lens to Micro Four Thirds (MFT, M4/3) Mount Mirrorless Camera Body : Electronics
B4 TV Lens to Sony Alpha E-Mount Camera Body Adapter – Fotodiox, Inc. USA
Blackmagic Design B4 Lens Mount for URSA Mini PL CINEURSAMTB4
B4-mount - Wikipedia
B4 Cine Lens to Micro Four Thirds (MFT, M4/3) Mount Mirrorless Camera Body Adapter – Fotodiox, Inc. USA
B4-mount - Wikipedia
Used Blackmagic Design URSA Mini - B4 Mount | MPB
Pairing an Ursa Mini 4.6K with a Canon B4-mount ENG zoom
2/3" B4 Mount Lens to Sony E mount with built in 2X glass adjustable adapter | eBay
Sony Introduces a B4 Mount for FS7 / FS7 II – Complete Your S35 ENG Kit | CineD
2/3" B4 Mount Lens to Hasselblad X mt adapter with built in 3X glass adjustable | eBay
B4 2/3" CANON FUJINON Cine Lens to RED Square Mount Cinema Camera Adap – Roxsen.com
Amazon.com : Fotodiox Pro Lens Mount Adapter, B4 (2/3") Lens to Sony NEX (E- Mount) Camera Body, for NEX-3, NEX-3N, NEX-5, NEX-5R, NEX-6 NEX-7 : Electronics