Piston o-ring for:Gilson Pipetman Classic 100μL (P100)Rainin Classic 100μL (PR100)Gilson Pipetman Fixed F25, F50, F100Gilson Pipetman Neo 100μL (P100N)Alternative to Gilson F161805, F144496, Rainin 400067, 17003384, 17003448.With 90100, alternative to Gilson set F144864.Made in the USA