In the UK anglers still use traditional (read slightly dated and quirky) methods of calculating the cocking weights of their floats using split shot, origionally derived from the world of shotguns and bird shooting. 

However, for my European customers and anyone else happier to work in metric (grams), here is a convenient split shot to gram conversion chart which also helps show the replationship between the different shot sizes. If a float is marked as 1SSG, you could use 4BB or 3BB + 2x No4 - as long as they add up to 1.6g - they are all the same!

1 x SSG	=	1.6G	or	2XAAA
1 x AAA	=	0.8G	or	2XBB
1 x BB	=	0.4G	or	2X4
1 x 1	=	0.3G
1 x 4	=	0.2G	or	2X6
1 x 6	=	0.1G	or	2X8

In more detail below

1x No1	=0.3g	1xBB	=0.4g	1xAAA	= 0.8g	1X SSG	= 1.6g
2x No1	= 0.6g	2xBB	=0.8g	2XAAA	= 1.6g	2X SSG	3.2g
3x No1	=0.9g	3xBB	=1.2g	3XAAA	= 2.4g	3X SSG	4.8g
4x No1	= 1.2g	4xBB	= 1.6g	4XAAA	= 3.2g	4X SSG	6.4g
1x No4	=0.2g	5xBB	= 2.0g	5XAAA	= 4.0g	5X SSG	8.0g
2x No4	= 0.4g	6xBB	= 2.4g	6XAAA	= 4.8g	6X SSG	9.6g
3x No4	= 0.6g			7XAAA	= 5.6g	7X SSG	11.2g
4x No4	= 0.8g					8X SSG	12.8g
5x No4 =	= 1.0g					9X SSG	14.4g