Floor Springs Our high durability, fire rated floor springs with concealed mounting and Cam-Motion® system are suitable for wood, glass, metal and fire rated doors. Cam-Motion® technology enables floor springs to comply with CEN TR 15894 requirements and ensures that the force which a user needs to apply to open the door up to 60° must be reduced by 40%. DC475 - Floor Spring Floor Spring with Cam-Motion® technology and adjustable c… DC477 - Floor Spring Floor Spring with Cam-Motion® technology and adjustable c… DC450 - Floor Spring Floor Spring with Cam-Motion® technology and fixed closin… DC430U - Floor Spring Floor Spring with Cam-Motion® technology and fixed closin…