The Shimano Di2 Frame Grommets secure internally routed E-Tube wires where they enter frame.
Each set includes four rubber grommets. Choose SM-GM01 or SM-GM02 models*.
*The SM-GM01 model is a 6mm circle. The SM-GM02 is a 7x8mm oval. If you're unsure which to order, your frame manufacturer should be able to tell you which fits your bike.