Welcome to the forum. Although you can post in any forum, the USA forum is here in case of local regs or laws
Are you meaning the Geberit ones?The black rubber ones are ok
Are you meaning the Geberit ones?
Reply to the thread, titled "Best flush cones for low level cistern connections?" which is posted in Bathroom Advice on Plumbers Forums.
We recommend City Plumbing Supplies, BES, and Plumbing Superstore for all plumbing supplies.