Middleburn XC Spider The new Compact Driver XC spider has been machined similarly to the old RS8 spider but is a completely new spider & is laterally stiffer. The new 4-arm XC spider has been remodelled allowing us to machine more metal away on both the front & back of the spider. The weight has been reduced to 58g without losing any strength. Chainline is 48mm using a 113mm bottom bracket. Available in Black, Silver, Red & Blue Replaces the RS7 Compact Drive spider & the RS8 spider The ATB XC spider is a new name for the RS7 ATB spider, there are no changes to the spider.