SRAM Tool Bleeding Edge - For Use With Avid Pro Bleed Kit -† S4/Monoblock Calipers, Guide Ultimate/RSC (B1)/RS (B1)/R (B1)/Level ULT/Level TLM:

New bleed porting and fluid path make it easier to push fluid through the caliper for quick and easy bleeding, dedicated bleed adapter for the S4 caliper plugs into the bleed port and seals the system to minimize air contamination and fluid loss.