Yeah I posted them there this is not the same as SFY.. SFY plugs are about a 1/4" thick.. these are around 1/16" at the most.. its the same material as SFY but I'm using it like I did with the ZFM.. the silicone caps in the ZFM mod are to firm for the bridge to actually penitrate...The plugs I'm making now are thiner then the silicone caps on your carts... its more like a membrane then a plug... It allows for the bridge to penetrate and touch the fluid in the reservoir.