These are tuning spools for Shimano 17Conquest BFS reels.
17CNQ15R spool is to upgrade casting performance for light, rigs in 3-5g. Spool weight 5.1g. Please add 4pcs of 1mm thick neodim magnets listed on this page or brake will be too little.
17CNQ29R spool is a deeper spool with 50% more line capacity than stock spool. 5.3g (genuine spool 7.9g)
Line capacities
Genuine spool 0.235mm-45m
17CNQ15R(1.5mm deep spool) 0.165mm-45m, 0.205mm-35m
17CNQ29R(2.9mm deep spool) 0.235mm-60m, 0.260mm-50m, 0.285mm-40m