# Gripper Thumb Bionic Attachment
![Gripper Thumb Bionic Attachment.jpg](file-guid:59115dbb-e5a3-4165-a097-eb56267d849d "Gripper Thumb Bionic Attachment.jpg")
To learn about what each of the above icons represents, please refer to the [Device Ratings Guide](wiki:/s/e-nable-devices/wiki/page/view?title=Device+Ratings+Guide "Device Ratings Guide").
**Designers:** Eric Bubar (remix of Skip Meetze’s Gripper Thumb Terminal Device)
This design is an attachment for a voluntary opening, gripper-style terminal device. It allows for attaching a high-torque servo, Arduino Nano, and rechargeable batteries to the back end of a terminal device to actuate a cable that will pull the voluntary opening device open. It has been tested on a gripper thumb terminal device design from Skip Meetze and the TuuTree terminal device from Fricis Pirtnieks. The design is thoroughly documented with photos, instructions and a list of materials.
Please share your feedback in the comments below!
# Files and Resources
STL Files: [Link](https://www.prusaprinters.org/prints/7124-gripper-thumb-servo-attachment)
Source CAD Files: Not available
Assembly Materials Kit: Not available
Video Tutorial: [Link](https://www.youtube.com/watch?v=iGfVgaTxcCc&t=162s)