Shimano (D-type 4-piston) Pads,TRP Quadiem, Gold

Gold (HH): Super-high friction, high heat (longer lasting) sintered bronze metallic compound with diamond ground surface for wet/extreme conditions (due to high heat generation, HH-Gold compound is not for Hydraulic/DH race use unless OE specified)
Red (R): High friction, low heat (faster wearing) aramid based, semi metallic soft compound for DH racing

Green: Med-high friction (medium wearing) aramid based compound for XC/all purpose (No Squeal)

Shimano (D Type 4 Piston) M9120/M8120/M8020/M810/M640/MT520/MT420/U8020; TRP Quadiem/SL/SlateT4; Tektro HD-E725/HD-M735/HD-M745/HD-M750