Timers control the on/off time of your electronic products. Contactors regulate power surges and protect your equipment from damage, preventing blown fuses etc. Light accessories contains eye protection, light movers and lights you can use when your ballast/led's are off, without harming the plants. Light controllers do many things like mimic sunrise and sunset. lower power to the lights if its too hot, change light colour spectrum and many other things. Then theres cables plug and socket spares of various types.