I have replaced a few of these lights replacement in kitchens. Often it is the 230V fluorescent tube “link” types that have failed where I simply replace with fairly inexpensive KSR manufactured units. But the halogen 20 watt 12V units with broken push in lamp connectors or broken lenses may as well be scrapped and replaced with LED lamped models. Sure you can buy direct replacement 20 watt Halogen fittings for £10, but why bother with all that hassle of changing those fiddly lamps and it is a waste of energy. The replacement LED versions only use 3 watts of energy and produce 150 lumens of light which is similar to a 15 watt Halogen lamp. Again KSR make a nice one, and KSR are a company local to my business in Horndean See http://www.ksrlighting.com/lighting/Kitchen-Undershelf.html.