This is an all world ETF which includes also small caps unlike regular MSCI ETFs which only have Large and Mid Caps listed.
The MSCI ACWI IMI Index is a free float-adjusted market capitalisation weighted index that is designed to measure the equity market performance of developed and emerging markets. It covers c.9000 securities across large, mid and small cap size segments and consists of c.45 country indices, of which approximately half are developed and half are emerging markets.
ISIN IE00B3YLTY66