Holland Systems sell wireless lone worker alarms, panic alarms, paging and remote monitoring systems. Specialised Emergency Call Buttons: Looking for a solution to your safety needs for your leisure facility or swimming pool, our range of wireless Call Buttons will provide a versatile and affordable solution.Wireless Video Security: Metal thefts are causing thousands of pounds worth of damage and disruption to property. Repair costs and loss of service are much more expensive than the actual cost of copper and stolen materials.