Updated Feb 5/2018
Cable Locks and Protectors
SmallHD Canon 5D MKII Port Protector - Reg $65 SALE
$39 - limited stock
Tired of your HDMI cable popping out of your 5D Mark II? Here is a low-cost and light-weight accessory to help. Made out of plastic, it attaches to the side of your camera. Locks the HDMI cable in place. Does not use the 1/4 screw hole on the bottom of the camera. Comes with a miniHDMI-HDMI cable (18"). Compatibility - only works on the Canon 5D Mark II. Cannot be used with a battery grip.
SmallHD Canon 5D MK III Port Protector - $75 - special
Same as the above, except works with the Canon 5D Mark III.
Small HD Port Lock - Sale $5 - limited stock
Lock down your cables and protect your monitor's ports with the DP4 HDMI Port Lock. Milled from Aluminum, this device is lightweight and low profile. Held firmly in place by any number of mounting options. Test fit recommended before purchase.
Find more DSLR cages here