Transponder mount for many cars are available:
https://lapmonitor.com/store/en/18-transponder-mount
Some free 3D model for transponder mount are available for printing:
https://www.thingiverse.com/LapMonitor/designs
Traxxas
Slash
Please check this video:
https://www.youtube.com/watch?v=wfo4-UcSRcY
Rustler
Transponder model used is ref: TP_JST_01
Buggy 1:10th
B6.x B7 2WD Team Associated Transponder holder
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XB2 Xray Transponder holder
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Other 2WD examples
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XB4 B74 YZ4 Transponder holder
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Buggy 1:8TH Brushless
Team Associated RC8B3e
Mugen MXB7/8
Free 3D model: https://www.thingiverse.com/thing:3005753
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Carbon version
Tekno EB48 2.0
Kyosho MP9e MP10e
Free 3D model: https://www.thingiverse.com/thing:4568733
XRAY XB8e / TLR-XE /Hobao VSE/SSE
Carbon version
Free 3D model: https://www.thingiverse.com/thing:4300695
Generic solutionBuggy 1:8TH nitro
KYOSHO MP9/10
XB8
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