Well, don’t buy anything that says 23mm tubes or holes. Those are not for 125 Shifters. The boxes for the 125 classes will be 29 or 30mm tubes. Personal preference…if you have to run an Air Box, the KG Ape http://www.shop.eshifterkart.com/KG-APE-30mm-Air-Box-Filtered-Intake-Silencer-FA003AG.htm
The KG is very expensive so a lot of guys also like the straight Freeline and the RLV 4 hole (which you have pictured above). Either way, you loose top end. Unfortunate some tracks, including ours, require the Boxes.