Part number: ALM RY451
ALM Manufacturing spool and line, spool cover and spring

Suitable for the following Ryobi models 

RLT2523, 
RLT3025F,
RLT3025S, 
RLT3123, 
RLT3525S, 
RLT3525SPKF

Spool supplied with: 
1.3mm trimmer line 
2 x 3m

Compares to: RAC118 

Note
If you lose the plastic spacer attached to the original spring, you will need to stretch the replacement spring a bit to lock the spool in place properly or line will feed out uncontrollably