I have a Shape rig that I'm not using, so I wanted to try to share it with others. It's in great shape because so far I've just tested it around the house.

Here's the official description:
The Canon C100 C300 C500 Shoulder Mount from SHAPE is a shoulder rig with light weight support (LWS) for the Canon Cinema EOS line of movie cameras. As the three have a similar profile, this rig is compatible with the C100, C300and C500 models. The base plate features specially recessed rods to accommodate the these cameras' uniquely tall stature while ensuring proper centering of lenses in case a matte box is used.

The system includes 15mm rods with the standard LWS spacing of 60mm. Because rod-based accessories are standardized you can use virtually any 15mm accessories for LWS you want with this rig. Types of accessories include, follow focuses, matte boxes, mounts for external audio and video recorders, EVFs, battery plates, cages and more. The included rods are 12" in length and can be extended if needed.

Handles and a shoulder pad allow you to use the Canon C100 C300 C500 Shoulder Mount on a tripod or hand-held. The handles feature rosettes and spring-loaded push-buttons so that the angle can be adjusted on the fly without having to loosen a screw. Both the hand grips and the shoulder pad clamp onto the rods using a single red knob that ratchets in case you can't turn it a full circle. Extension rods can be added behind the shoulder pad for attaching weights, battery plates, or other accessories intended for behind the camera or to help balance the load.

Shape Shoulder Mount Features

Quick Handle Rod Block: Padded for operator comfort
Quick Handle Rod Block: Can be left on rig even when using a tripod
Quick Handle Rod Block: Mini Composite Shoulder Pad: Single red knob for adjusting and securing the shoulder pad
Quick Handle Rod Block: Secure the handles by tightening a single knob on one side of the Rod Block
Quick Handle Rod Block: Achieve precise positioning by sliding Rod Block along the rods
Quick Handle Rod Block: Push button 360deg. rotating handles for fast set up adjustments
Base Plate: Tripod mountable with 3/8"-16 or 1/4"-20 screw
Base Plate: Ratchet keys located on the both sides of the Base Plate secure the 15mm rods
Quick Handle Rod Block: By attaching extension rods to the back, weights such as the SHAPE Base Counter-Weight can be added
Support System: Compatible with nearly all 15mm rod accessories that feature 60mm center-to-center LWS (light weight support) spacing
Base Plate: Recessed rod height to ensure proper centering of matte boxes relative to lens
Support System: Features a pair of 15mm rods that are 12" in length
Support System: Made specifically for the Canon Cine EOS C100, C300and C500 cameras
Base Plate: Attaches underneath the camera with four M4 screws (included) or using with 3/8"-16 and 1/4"-20 screws (also included)