This is a replacement joystick knob for a large variety of different powerchairs. There are 2 versions of the T-handle, an angled one and a straight one. The angled one is ergonomically designed to match the resting angle of a persons wrist/hand. If you aren’t sure which one will be the most comfortable for you there is an option to purchase both at a discount. The hole is 1/4″ in diameter; however, if you need a different hole diameter, please let me know. I can adjust it. There is a screw on the back of it, so it can be tightened. We can confirm fitment on the following models; however, you should still measure the joystick shaft to make sure it is ¼” before ordering. Permobil F3, Permobil F3 Corpus, Permobil F5, Permobil Koala, Permobil M3, Permobil M3 Corpus, Permobil M5, Permobil M300, Permobil 300, Quantum 3, Quantum Edge 3, Quantum Q6, Quantum Q6 Edge, Quantum Q6 Edge 2.0, Quantum Edge 2.0, Quantum Stretto Q-Logic 3, Quickie 646, Quickie 636, Jazzy Passport, Jazzy 7, Jazzy HD, Terra/Terra SX B+B Enjoy Mobility, Air Hawk Power Chair, Alltrack HD/HD3, Vive Mobility Foldable Long Range Transport Aid, MobilityPlus+ Ultra-Light, Invacare TDX SP, Scewo Bro, Fold&Go Magshock I can custom make all kinds of joysticks; if you would like something made, please message me.