Here are all the options parts for the Xray XB4 2020 and olders
Reference 06363124-M
Brand: XRAY
SUSPENSION ARM REAR LOWER LEFT - 3-HOLE - MEDIUM - 363124-M
Reference 06971032
Brand: XRAY
SILICONE O-RING 3.2x0.8 (10) - 971032
Reference 06368045-T
Brand: XRAY
TITANIUM SCREW SHOCK PIVOT BALL WITH HEX (2) - 368045-T
Reference 06303124-K
Brand: XRAY
ALU SHIM 3x6x2.5MM - BLACK (10) - 303124-K
Reference 06364962-L
Brand: XRAY
GEAR DIFF OUTDRIVE ADAPTER - LIGHTWEIGHT (2) - XRAY
Reference 0148202
Brand: HIRO SEIKO
XB4'18 Titanium Hex Socket Screw Set - 48202
Reference 0148401
Brand: HIRO SEIKO
XB4'19 Titanium Hex Socket Screw Set - 48401
Reference 06303120
Brand: XRAY
SET OF ALU SHIM (0.5MM, 1.5MM, 2.5MM) - 303120
Reference 06303123-O
Brand: XRAY
ALU SHIM 3x6x2.0MM - ORANGE (10) - 303123-O
Reference 06303125
Brand: XRAY
ALU SHIM 3x6x3.0MM (10) - 303125
Reference 06306200-O
Brand: XRAY
ALU SERVO MOUNT - ORANGE (2) - 306200-O
Reference 06335081
Brand: XRAY
ALU DIFF PIN - HARD COATED (2) - 335081