If you damaged your screen or would just like to have a spare around this is the replacement screen for the USFS approved spark arrestor end cap insert BT-3 (Beta EVO two stroke models 125-300cc for years 2009-2020).
Part# RP-S-28 Technical Data:
PATENT PENDING & USFS APPROVED (REF. FILE#0880-01)
USFS approved replacement screen for BT-3
Screen-stainless steel
Weight- 3 grams/0.1 oz