PIP93097 Formula P3 Pinning Expansion .50mm by Privateer Press Formula P3 Pinning Expansion .50mm by Privateer Press Used for pinning delicate and thin models, this expansion set for the Formula P3 Modeling Drill provides smaller drill bits and brass rods to pin fine models. Refill set includes three .50mm drill bits and six .50mm brass rods in six inch lengths.