LEGO Support 4 x 4 x 5 Stanchion with Standard Studs (2680)

has been used in at least 2 LEGO sets over the past 25 years, since it was first used in 1999.

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The Yellow Support 2 x 4 x 5 Stanchion Inclined, 5mm wide posts was released in 1983 and has been used in 4 sets to date in the following categories

Lego Parts: Support 2 x 4 x 5 Stanchion Inclined, 5mm wide posts (PACK of 4 - Yellow)

LEGO Support 4 x 4 x 5 Stanchion with Standard Studs (2680)

LEGO 6990 Monorail Transport System Set Parts Inventory and Instructions - LEGO Reference Guide

Peeron: Rebel Hunter (#6897-1)

LEGO Part 2680 Support 4 x 4 x 5 Stanchion (Black)

KEY TOPIC] LDD New Parts - Digital LEGO: Tools, Techniques, and Projects - Eurobricks Forums

New Parts for LGEO Library - Digital LEGO: Tools, Techniques, and Projects - Eurobricks Forums

LEGO SUPPORT STANCHION, 4 x 4 x 5, Tall Studs, No: 2680, 9 Pieces, Monorail £17.99 - PicClick UK