Inverted Bucket Traps: Series 900 is offered by Forbes Marshall. Forbes Marshall is an ISO 9001 certified company that manufactures engineering products for process industries across the world. Series 900 ranges of IBST or inverted bucket steam traps is designed for mounting in vertical pipe work between flanges. With forged steel body and cover, these Inverted Bucket Traps: Series 900 are suitable for high pressure applications and incorporate an integral check valve fitted in the inlet tube. The Inverted Bucket Traps: Series 900 are available in DN 15, DN 20, DN 25, DN 40 and DN 50 sizes.