A food grade silicone o-ring for use with the Cafelat Robot portafilter plate. 

From time to time the silicon o-ring may require a quick rub of a food grade lubricant such as Dow 111. The o-ring requires just enough Dow 111 to give it a 'sheen'.

Warnings: Do not remove the o-ring from the plate unless you plan on replacing it, removal may damage the o-ring permanently