Specially shaped, curved, and interlocking concrete blocks for Water Tank construction, which are produced using mechanical vibration.  They can be made with a low cement content, but still achieve high structural strength.

Water Tanks can be built mostly without the need to use reinforcement and are very durable.

The durability of Parry Multivibe tanks surpass that of steel or steel-reinforced tanks because they do not contain corrodable materials.  Also, Multivibe tanks do not contaminate their contents, so it is possible to collect and store drinking water.

Water Tank production with Multivibe  interlocking blocks does not require special materials or skills.  To construct a tank holding 6,000 litres should take as little as 2-3 days.

The blocks are also useful for well construction  and components for pit latrines.  Other applications include cattle troughs, culverts, arches and vaults.

The block mould is a casting mould, which means the mould is removed whilst the concrete is still wet, allowing the mould to be used repeatedly during the same day.  The steel moulds are filled with concrete, vibrated and removed, leaving the block standing on the floor.

In practice, one Multivibe with one mould will produce around 80-100 blocks per day, with a possibility of increasing this to 160-200 blocks per day with the addition of a further mould.

A typical Water Tank Block plant consists of:

1. Multivibe vibrator
2. Small accessory pack
3. One of three different water tank moulds – 2m, 3m or 4m.

An additional demould-assist accessory is available where producers have to work with extra-sticky materials.