This is a wireless antenna bar for the A1708 2016 2017 & A2159 laptops, If there appears to be lag or connection issues then the antenna components are one possible cause of the problem and will most likely need to be replaced. This assembly mounts to the inside of the bottom cover assembly, includes two (2) antenna cables. Compatible Part Number(s): 817-1246-10-1 A P/N: 923-01169, 923-01389 WLAN Antenna Connector: U.FL, Plug In Reference Compatible with models: for A1708 2016 2017 - MacB00kPro13,1 A1708 Late 2016: BTO/CTO (2.4GHz Core i7 8GB) (Space Grey) EMC: 2978 - MacB00kPro13,1 A1708 Late 2016: BTO/CTO (2.4GHz Core i7 16GB) (Silver) EMC: 2978 - MacB00kPro13,1 A1708 Late 2016: MLL42LL/A (2.0GHz Core i5 8GB) (Silver) EMC: 2978 - MacB00kPro13,1 A1708 Late 2016: BTO/CTO (2.4GHz Core i7 8GB) (Silver) EMC: 2978 - MacB00kPro13,1 A1708 Late 2016: MLL42LL/A (2.0GHz Core i5 8GB) (Space Grey) EMC: 2978 - MacB00kPro13,1 A1708 Late 2016: MLL42LL/A (2.0GHz Core i5 16GB) (Silver) EMC: 2978 - MacB00kPro13,1 A1708 Late 2016: BTO/CTO (2.4GHz Core i7 16GB) (Space Grey) EMC: 2978 - MacB00kPro13,1 A1708 Mid 2017: MPXQ2LL/A (2.3GHz Core i5 8GB) (Space Grey) EMC:3164 - MacB00kPro13,1 A1708 Mid 2017: BTO/CTO (2.5GHz Core i5 8GB) (Space Grey) EMC:3164 - MacB00kPro13,1 A1708 Mid 2017: MPXQ2LL/A (2.3GHz Core i5 16GB) (Silver) EMC:3164 - MacB00kPro13,1 A1708 Mid 2017: BTO/CTO (2.5GHz Core i7 16GB) (Silver) EMC:3164 - MacB00kPro13,1 A1708 Mid 2017: MPXQ2LL/A (2.3GHz Core i5 16GB) (Space Grey) EMC:3164 - MacB00kPro13,1 A1708 Mid 2017: BTO/CTO (2.5GHz Core i7 16GB) (Space Grey) EMC:3164 - MacB00kPro13,1 A1708 Mid 2017: MPXQ2LL/A (2.3GHz Core i5 8GB) (Silver) EMC:3164 - MacB00kPro13,1 A1708 Mid 2017: BTO/CTO (2.5GHz Core i7 16GB) (Silver) EMC:3164 for A2159 2019 - Macb00k Pro 15,4 13'' A2159 2019: MUHN2LL/A* (1.4GHz ''Core i5'') EMC: 3301 - Macb00k Pro 15,4 13''