Command B4J4-0003 BT40 Jacobs Taper Tool Holder Adapter is a compact interface that bridges BT40 spindles with Jacobs-taper tool holders. Identified by part number B4J4-0003, this adapter enables Jacobs-taper tooling to be used in BT40 setups. It serves machinists who need to swap between BT40 tooling and Jacobs-taper tools without changing spindles or holders.
