Brookfield PFT Powder Flow Tester Operating Instructions Manual page 69

Insert the horseshoe shape foam collar (PFT-104) over the Lid and Trough.
6)
NOTE: Flex the collar to an open position when installing around the
bellows to ensure that the bellows do not deform.
Secure the access door for the bubble level by using plastic shrink wrap or tape
7)
that will not damage the paint. Secure the foam collar with plastic shrinkwrap or
Velcro Strapping (Part Number PFT-115), which is also supplied in the Repack Kit.
Access Door for Bubble Level
AMETEK Brookfield
Bellows
Page 69 Manual No. M09-1200-F1016