Thanks for your reply,
I meant to say 'Bosch Blue Line Gen 2 BLD2 Pet TriTech' pir, bought two of these last August from Security Warehouse and have been pleased with them.
also, any idea which fire detector might be best, I'm fitting them to a commercial property I'm renovating, one will go into the shop area the other into a unheated storage area.
will put together my order tonight.
thanks again