The "magnetic bases" include a main pole with one or two sub-poles for mounting devices. Part number 69-0230 also includes a flexible pole with a holder for an 8mm rod

The "magnetic holders" have a center tap hole to accommodate poles, but they are not included.

The term 'magnetic holders' can also refer the various hold-downs used with our Recording and Imaging Chambers to secure perfusion tubes, culture dishes, etc.