Just wondering if anyone knew off the top of their head. I think it's a 10mm for the bleeder valve but it's been several months since I last touched it. I could easily find out for myself but just wanted to get some confirmation. Gonna go get a flare nut wrench specifically for the bleeder valve. And if anyone here is bleeding their own brakes I highly recommend a flare nut wrench. Will help prevent you from stripping the nut. Came close to doing that on another car using a normal open end wrench.