These sets consist of high temperature heat resistant, silicone gray dust boots and high temperature pressure seals, manufactured by Frenkit Performance for most late-model Brembo calipers. These are the perfect components for street and track-oriented performance vehicles!
 
These are silicon dust boots and high temperature pressure seals and are recommended for track/racing/high performance driving events.
 
Included are the following components:
28mm (28 mm) High Temp Gray Silicone Dust Boot, Part Number 750.99000, Quantity 2
28mm (28 mm) Pressure Seal, Part Number 753.99000, Quantity 2
30mm (30 mm) High Temp Gray Silicone Dust Boot, Part Number 750.99001, Quantity 2
30mm (30 mm) Pressure Seal, Part Number 753.99001, Quantity 2
 
This is also StopTech kit part numbers:
143.99028K
143.99030K
 
This seal kit replaces OE Brembo Dust Boot part numbers:
20.4872.40 (20 4872 40) - 28mm
20.4872.41 (20 4872 41) - 30mm
 
This seal kit replaces OE Brembo Pressure Seal part numbers:
05.5955.52 (05 5955 52) - 28mm
05.5955.53 (05 5955 53) - 30mm
 
This seal kit replaces OE Brembo Rebuild Kit part numbers:
105.5955.52 (105 5955 52) - 28mm
105.5955.53 (105 5955 53) - 30mm
 
Typically on a 4-Piston caliper, there are two of each piston size, so this combination should service one caliper (4 pistons total).  These are not application specific, rather for those who may have a single torn dust boot or failed pressure seal or for those who are rebuilding their calipers; however, this kit will may work for many aftermarket Brembo or StopTech 4-piston caliper combinations.