Card thickness
Thickness is quoted in mil, thousandths of an inch. 30 mil is the standard ISO CR80 credit-card thickness and is what almost every card printer, badge holder, slot punch and access reader is designed around — specify it unless you have a reason not to. 15 mil cards are thinner, cheaper, and suited to short-life uses such as visitor passes and event badges where the card is issued, worn for a day and discarded. Mixing thicknesses across a site is a false economy, because holders and readers are sized for one or the other.
Magnetic stripe and colour stock
Magnetic stripe cards are ordered by coercivity. Low-coercivity stripes are easier and cheaper to encode and are fine for short-term or low-security use, but they are more readily erased by contact with everyday magnets. High-coercivity stripes hold their data far better and are the right choice for a credential someone carries for years. Plain white PVC takes full-colour dye-sublimation printing; pre-coloured PVC stock is useful for colour-coding departments, contractor grades or access levels without spending printer ribbon on a solid background.
Order cards and ribbon together
Card stock and ribbon are consumed in step, and a printer with cards but no ribbon is as stopped as one with neither. Work out your annual issue rate, then order both against it. Card printers are also sensitive to stock: use cards intended for your printer to avoid feed faults and head wear.
Brands
Zebra, including the Premier PVC range in 30 mil and 15 mil, and Evolis.
Trade pricing and business accounts are available for UK organisations, and bulk orders are welcome — request a quote.