high visibility Saftey Yellow smaller diameter shaft accommodates all popular calibers down to .177 cross section design makes the OCI much more flexible and easy to use tapered point allows the OCI to be inserted in the breach and down the barrel more easily meets NRA guidelines RANGEQUIP OCI's are designed for gun enthusiasts everywhere. They're a simple sure-fire way of idicating the chember is clear. We encourage every gun owner to use an OCI any time a gun is being used in a public place, even on display at gun shows or simply on the bench at home. A simple assumption that the chamber was clear has resulted in countless unnecessary accidents through the years