OPTIMUM PERFORMANCE or  "OP" 
100% Wool Knitting Yarn from New Zealand

Yarn is PARTIALLY FELTED but knits is any similar weight knitting product
Provides high strength, though very soft, AND high resistance to pilling

500 gram lots -- 5 100 gram skeins of any one shade

2 weights: DK to Worsted (5.5 or 5 sts/in, 226 yds) & Chunky (3.5 or 4 st/in, 140 yds)
400 series is the lighter weight; 300 series is heavier weight
ie 2 numbers w/shade preceded by 4 or 3 indicates desired weight
thus, 402 would be worsted weight in black

With each yarn weight:  3 options for gauge with a change of needle size 

2nd & 3rd shade cards are more representative of actual colors
1st card has better focus to read the printing which you should be able to enlarge 

Price is for 5 100gm skeins all one shade of your choice in an email after purchase
Add'l 5 skein lots in other shades at your discretion to benefit with combined shipping