Tamiya has released Rubber Anti-Slip Sheet 25mm x 130mm OP-1694 in No Scale scale under Adhesive / Tape category
This synthetic sheet will be to be sandwiched between your framework and battery pack to prevent slippage and wobble, additionally during aggressive drives! Of them costing only 0.2mm dense it is actually unobtrusive, and it has now one adhesive part for a detailed fit. Proportions: 25x130x0.2mm
Compatible Chassis
TA07 PRO, TRF419, TRF419X, TB Evo.7, TB Evo.6 and TB Evo.6 MS Chassis