Next you need your fixing dimensions. Measure your top plate dimensions in order to match any replacement castors. Alternatively measure your bolt dimensions or your threaded stem size. Also measure your fixing bolt size D1 shown in the graphic on screen. At Ross Handling we can supply fixing bolts and nuts. In order to measure thread size simply measure the diameter of the thread. 8mm diameter equates to a m8 thread. Top plate castors are fixed to your unit by four fixing bolts per castor. 

Supplied separately. Bolt hold castors can attach either by using a threaded bolt or a tubular adapter. Threaded stem castors are supplied with a stem that can screw into your equipment. Heard the one about square pegs into round holes? Attaching castors into round and square tubes can be achieved by using bolt hole castors and castor tube adapters. We have a variety of sizes available in both square and round tubular expander fittings. To find out more just speak to a member of our team. Next you need to choose the right wheel material. As a general rule of thumb, its hard wheels for soft floor surfaces, and soft wheels for hard floor surfaces. Soft wheels are rubber and hard wheels are nylon and polyurethane. Pneumatic and puncture proof wheels also available from Ross Handling are ideal for outdoor applications. Then you need to decide the castor configuration: Swivel, swivel with brake, or fixed.