... , inside black, surface white, corrugated with cuffs smooth Drain pipes used for air-conditioners features: 1) PE material, inside black, surface white ... , corrugated with cuffs smooth 2) ID: 16 / 18mm, one side can be insert to the ... 3) Two specifications: ID. 14mm - OD. 19mm and ID. 16mm - OD. 21mm 4) Used in the air conditioner as drain pipe Packing ...