Model 61系列空氣放大器常見型號有：
Models 61H   Models 61L   Models 61F  Models 61FE   Models 61VH

61系列升壓繼電器以1:1的比例復制的氣動信號的應用中，輸入隔離或增加的流量要求。

The series 61 Booster Relays reproduce pneumatic signals in a 1:1 ratio for applications where bbbbb isolation or increased flow capacity are required.

61vh是一種高容量升壓繼電器設計用于對控制閥等執行器，需要非常快的開關速度。無論是61H和61vh特征穩定的旁路針型閥的輸入和輸出之間，從而消除了對外部管道旁路的需要.

61VH is a High-Capacity Booster Relay designed for use on control valve actuators that require very fast stroking speeds. Both 61H and 61VH feature a stabilizing bypass needle valve between the bbbbb and output, which eliminates the need for an externally piped bypass.