1. Stack material higher grade / lower temperature rise/ high performance.<br> 2. Commutator copper grad higher and small bar to bar surge lead to lower spark and higher endurance.<br> 3. Copper wire grade 2 endurance for high temperature.<br> 4. Epoxy resin to protect the copper wire from moving to avoid burning for big vibrarion hammer.<br> 5. Shaft mater better on hardness and gear.<br> Different batches may have slight color differences or differences in the actual product, which will not affect the use<br> Notice: The blades color is random, cannot be chosen the specified color.<br> Colour:Photo Color<br> Material:copper+Plastic<br> Package Contents:<br> 1x Armature Rotor Anchor Replacement<br> Only the above package content, other products are not included.<br> Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.