its an egg but, my hoss gets sset in his mouth quite easily so i've gone for the loose ring version, just ordered it so can't offer an opinion yet, sorry
He is very fussy in his mouth and doesn't work well into a contact but this bit has worked wonders!!! He also has very sensitive skin and gets bit rubs very easily but the curved mouthpiece of the RS means he hasn't had any problems with this since I started using the bit 4 months ago.