SRAM Reverb Stealth Service Manual page 27

Remove the internal floating piston (IFP) from the upper post. Insert
3
seven to nine plastic cable ties (cable tie size may vary), one at a time,
into the upper post and through the center of the IFP.
Pull the cable ties out of the upper post and remove the IFP.
Discard the IFP.
Plastic Cable Ties
A2
B1
Upper Post Disassembly 27