2904 Series Hole Reducer (4mm ID x 14mm OD) - 4 Pack

This hole reducer fits in a 14mm hole and reduces the bore to 4mm. The reducer protrudes 1mm into the 14mm hole so that a pair of them can clad a part with 2.5mm thickness, such as U-Channel or Low-Side U-Channel, and tightly squeeze down on the channel.