Pickup Springs 1.5mm Axles (48 Pack) 48 springs sized perfectly for zero friction addition when used to add power pickup on 1.5mm axles (N scale and P4 standard size). They are a delight to use. _ Simply remove one wheel add the spring and replace the wheel-set making sure you note which wheel is to the track. Drill a small hole in the floor of the coach/tender/caboose etc and solder a bit of fine wire to the tag end on the spring. Connect the wire to your flickerfree or loco pickups etc. You will be delighted these friction-free pickups. They will add nothing to the drag at all and will always be able to give perfect pickup as long as you keep track and wheels reasonably clean.