These knobs are alternatives to the pull handles used on the majority of enclosures. They are smaller and less obvious, thereby minimizing the amount of hardware on the door. This small size also makes them slightly more awkward to use and grab with wet hands. They are installed back-to-back (one inside and one outside) as well as being available in combination with a towel bar; typically towel bar outside, knob inside.

These knobs are also used on frameless sidelites as a "hook" to hang a robe or towel while in the shower.

Sonata Knob