MAINTENANCE
Hop Up rubbers should be cleaned with alcohol. They must not be lubricated in the internal area, where you contact BB. To clean, whenever possible, they must be removed from the pipe. If you don't know or can't disassemble, you can clean it with the pipe. Hop Up rubbers must be cleaned whenever the pipe is cleaned.
DURABILITY
The durability of a rubber varies a lot depending on the energy being used, the number of shots the gun takes and the way the gun is stored. Depending on these factors, it may have to be changed every 2 years or every 5 years.
ASSEMBLY
Each weapon is slightly different, but in general the Hop Ups are easy to assemble, and accessible to anyone who has some knowledge of airsoft weapon mechanics. However, it is easy to mount a rubber in a non-perfect way, thus sacrificing the performance of the weapon.