Download stock firmware for Leagoo Lead 3S smartphone from here or here.
Archive: Leagoo Lead 3S MTK6582-176078-20141006
Model: Leagoo Lead 3S smartphone
Project: rjk301_w_k450_d1_82
Config_version: V1.1.1
Baseband: _MT6582_S00_RGK301_REDUCE_BP_W_C1_V0_0_3_S0903_1_wg_n
Archive: Leagoo Lead 3S MTK6582-176078-20141006
Model: Leagoo Lead 3S smartphone
Image file size: 415 MB
Platform: Mediatek MT6582Project: rjk301_w_k450_d1_82
Config_version: V1.1.1
Baseband: _MT6582_S00_RGK301_REDUCE_BP_W_C1_V0_0_3_S0903_1_wg_n