The main objective of this study is to compare the compatibility among the different manufacturers (Thelma Biotel, Lotek Wireless, Sonotronics and Innovasea Systems) using the Open Protocols OPi and Ops. In addition, we will assess the impact of non-compatible equipment on receiver performance in different environments across Europe. OPi, OPs, R64K and Innovasea’s proprietary A69-1602 and A69-9007tags will be combined in these setups. Receivers and transmitters from the above mentioned manufacturers are used. Institutes from Belgium, Denmark, Portugal and Spain are involved in the study.