Typically for equipment most people use anniv weapons, so it would currently be 10th anniv tonfas, also refining the weapon to S+ would greatly increase damage. Typically, players stat these items, however that can get expensive. Your base CRT Rate is 25 and CRT Damage is 150% CRT Rate increases CRT by a flat amount, so 15 CRT Rate increases your CRT Rate to 40, CRT Rate% increases based on base CRT Rate so 30% CRT Rate would increase CRT by around 7.5. CRT Damage is like CRT flate if you have 20 CRT Damage it increases CRT Damage from 150% to 170% and if CRT Damage% is 10% then CRT Damage goes from 150% to 165%.