This new accessory from Excalibur greatly reduces the felt vibration and sound from your Excalibur crossbow. The new S5 sound and vibration suppression system attaches easily and quickly to the mounting holes in the riser of all of the 2004 and newer Excalibur crossbows. This new system is extremely simple and very durable and greatly reduces noise and vibration from your crossbow which will help you be more successful in the field.