oso slotOSO Sharp pro knife and scissor sharpener with suction cup for easy one handed use,perfect for straht and serrated knives with dedicated slot for scissor sharpening. (Black) Brand: OSO. 4.0 4.0 out of 5 stars 40 ratings.The Oso also stays true to the ultimate goal of the other speakers in the Artisan Series – the Nico Evo and Emma Evo – which is to provide excellent sonic performance at real-world pricing.