1.FR-4 green color solder mask single side pcb bare board; 2.Meet ROHS ... Blue, Red, Matt Green, Matt Black etc.Surface Finishing: Lead Free Hot Air Leveling (HASL), HAL;Immersion Gold (ENLG), Immersion ... Immersion Tin;Electronic Gold (Plate Gold), OSP, Gold Finger;Lead free HASL+ Gold finger, HAL/HASL/ OSP+ Carbon Ink, ... 10%double side pcb] FR-4 green color solder mask single side pcb bare board