Theragrippers On a Swab (image) Johns Hopkins Medicine Share Print E-Mail Caption A theragripper is about the size of a speck of dust. This swab contains dozens of the tiny devices. Credit Johns Hopkins University. Usage Restrictions None Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.