ICDR2 Polypipe 110mm Deep Inspection Chamber Base & 4 Risers UG437 Polypipe Chamber Base Shallow Access 320mm Dia Black UG440 Polypipe Chamber Base 220mm Deep x 460mm Dia Black ICDB1 Polypipe 150mm Deep Inspection Chamber Base & 4 Risers Black ICDB2 Polypipe 160mm Deep Inspection Chamber Base & 4 Risers Polypipe Four Riser (for Deep Inspection Chamber Base) 860mm effective height Black ICDR4 ICDB3 Polypipe 110mm Deep Inspection Chamber Base & 4 Risers PolySewer Chamber Base 460mm Terracotta PS670 (Inc Seal) ICDR1 Polypipe 215mm Deep Inspection Chamber Base Single Riser Black UG670 Polypipe 160mm Chamber Base 460mm Dia Terracotta