Montana Rail Link's Logan Local pauses in Sappington, Montana, at the beginning of the branch to Harrison so the Engineer can sign the Block Register. MRL's Harrison Branch (6th Subdivision) is Block Register Territory. Trains or maintenance-of-way crews must sign this register book prior to occupying the track. If no one else is registered, they fill out the required information to gain sole occupancy of the main track. If someone is already registered, they must contact that person and reach an understanding that the limits will be occupied jointly, and both must operate at restricted speed.