This slide block is used on earlier model B2700, B2900, and B2900F lifts.
If the carriage is louvered then the lift uses four of this block and four of the 4B31023 slide blocks per side.
If carriage is not louvered then it uses eight of the 4B31023 blocks per side.
How to determine which carriage your lift has:
Non-louvered carriages have lock dog 4B37081 while louvered carriages use lock dogs with spade bolt 4B37010 attached.
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