These are manufactured by German Stainless Steel and insulated by FDA approved nylon material.

Here are available sizes of Deaver Insulated Retractors.

FR:08-101, Deaver Insulated Retractor 0.75” x 7.0”   (1.9 cm x 17.7 cm) 
FR:08-102, Deaver Insulated Retractor 0.87” x 8.0”   (2.2 cm x 20.3 cm) 
FR:08-103, Deaver Insulated Retractor 0.63” x 8.5”   (1.6 cm x 21.6 cm)
FR:08-104, Deaver Insulated Retractor  1.0” x  9.0”   (2.5 cm x 22.9 cm) 
FR:08-105, Deaver Insulated Retractor  1.0” x 12.0”  (2.5 cm x 30.5 cm) 
FR:08-106, Deaver Insulated Retractor  1.0” x 13.0”  (2.5 cm x 33.0 cm)
FR:08-107, Deaver Insulated Retractor  1.5” x 12.0”  (3.8 cm x 30.5 cm)
FR:08-108, Deaver Insulated Retractor  2.0” x 12.0”  (5.1 cm x 30.5 cm)
FR:08-109, Deaver Insulated Retractor  3.0” x 12.0”  (7.6 cm x 30.5 cm)