Stranger strangergram guard sprocket oil slickeric lichtenbergers signature guard sprocket from stranger the strangergram is a standard style sprocket compatible with alll non socket drive cranks and is supplied with reducer tophats features construction 3d pentagram style custom design fully cnc machined from aircraft grade 6061 t6 alloy thickness4mm 6mm chain size 12 x 18 weight121gbuystranger componentsfrom chain reaction cycles the worlds largest online bike store