Dimensional phase stabilizer harness
From Jenny Everywhere Wiki
A dimensional phase stabilizer harness was a high-tech harness which would prevent its wearer from being involuntarily shifted by the likes of Jenny Everywhere. One alien gladiator wore such a harness to a fight to the death with Jenny, hoping to negate the advantage her powers gave her, but Jenny took this in stride, noting that the harness didn't prevent her from shifting other things around the gladiator. She thus used her powers to give herself scuba gear before shifting in a massive amount of water, flooding the arena. (PROSE: Jenny Everywhere Took My Breath Away)