LEGO 5106 Two-Way Valve and Non-Return Valve is a vintage Service Packs set from 1987 valued at $22 for new and sealed sets, up 527% from an original retail price of $3.49. Annual appreciation has averaged 3.39% since release. On the used market, values range from $9 to $11 based on condition.
LEGO 5106-1 Two-Way Valve and Non-Return Valve is a Service Packs Technic set released in 1987, containing 2 pieces. It includes a light gray pneumatic distribution block 2 x 4 with a non-return (check) valve and a light gray pneumatic switch with top studs. The components were supplied as spare/expansion parts for Technic pneumatic systems of the era, enabling airflow control and one-way flow within larger Technic builds.
A new and sealed Two-Way Valve and Non-Return Valve is currently valued at around $22, with annual growth of approximately 2%, which is lower than other Technic sets. The average used price is $10 for those in good overall condition. Based on current trends, this set could be valued near $23 within the next year.