I shared these little extended shaft D-ring screws in an earlier post, but here's the real reason why I have them around the studio. The extended shaft works great to mount accessories to your DSLR Video Cages, and the D-Ring makes tightening or loosening the screws easy without tools. Just yesterday I used these to mount my Sennheiser G3 Wireless Receivers to the GearBox directly to it's 1/4-20 mount without having to use an additional hot shoe adapter.
I can guarantee that these will work perfectly on the P&C GearBox Video Cages (found here), and also on the Kamera Tank Video Cages (found here). If you happen to have a different cage, the shaft on these screws are about 13mm so you can easily measure if these will work for you too. You can find these Extended Shaft D-ring Quick Release screws via eBay (Click Here).
D-Ring Extended Shaft Tool-Less QR Plate Screw