Actually, you cannot enter limit orders at 2.16, 2.17, 2.18, you can only enter order in 0.05 increments, however, if you enter a limit buy order at the ask and route it to BOX then your order may qualify for price improvement and you can get a fill like 2.16, 2.17, 2.18 or 2.19 or 2.20 if none...