Original XRAY spare and option parts!
There are several types of spool outdrives:
305134 - Springsteel - 8.28g - durable, heavy, allround solution
305135 - Composite - 4.00g - light, without blades, for stock semi-pro drivers
305136 - Alu - 3.56g - very light, with blades, for stock pro-drivers
305137 - Springsteel LIGHTWEIGHT - 6.71g - durable, best solution between durability and performance
305138 - Springsteel ECS BB - special solution for ball bearing drive shafts
All weights are for a pair - including blades if necessary.